xref: /external/chromium_org/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java

// Copyright 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package org.chromium.content.browser;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.SearchManager;
import android.content.ClipboardManager;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.content.pm.FeatureInfo;
import android.content.pm.PackageManager;
import android.content.res.Configuration;
import android.database.ContentObserver;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.os.ResultReceiver;
import android.os.SystemClock;
import android.provider.Browser;
import android.provider.Settings;
import android.text.Editable;
import android.text.Selection;
import android.text.TextUtils;
import android.util.Log;
import android.util.Pair;
import android.view.ActionMode;
import android.view.HapticFeedbackConstants;
import android.view.InputDevice;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.accessibility.AccessibilityEvent;
import android.view.accessibility.AccessibilityManager;
import android.view.accessibility.AccessibilityManager.AccessibilityStateChangeListener;
import android.view.accessibility.AccessibilityNodeInfo;
import android.view.accessibility.AccessibilityNodeProvider;
import android.view.inputmethod.EditorInfo;
import android.view.inputmethod.InputConnection;
import android.view.inputmethod.InputMethodManager;
import android.widget.FrameLayout;

import com.google.common.annotations.VisibleForTesting;

import org.chromium.base.ApiCompatibilityUtils;
import org.chromium.base.CalledByNative;
import org.chromium.base.CommandLine;
import org.chromium.base.JNINamespace;
import org.chromium.base.ObserverList;
import org.chromium.base.ObserverList.RewindableIterator;
import org.chromium.base.TraceEvent;
import org.chromium.content.R;
import org.chromium.content.browser.ScreenOrientationListener.ScreenOrientationObserver;
import org.chromium.content.browser.accessibility.AccessibilityInjector;
import org.chromium.content.browser.accessibility.BrowserAccessibilityManager;
import org.chromium.content.browser.input.AdapterInputConnection;
import org.chromium.content.browser.input.GamepadList;
import org.chromium.content.browser.input.ImeAdapter;
import org.chromium.content.browser.input.ImeAdapter.AdapterInputConnectionFactory;
import org.chromium.content.browser.input.InputMethodManagerWrapper;
import org.chromium.content.browser.input.PastePopupMenu;
import org.chromium.content.browser.input.PastePopupMenu.PastePopupMenuDelegate;
import org.chromium.content.browser.input.PopupTouchHandleDrawable;
import org.chromium.content.browser.input.PopupTouchHandleDrawable.PopupTouchHandleDrawableDelegate;
import org.chromium.content.browser.input.SelectPopup;
import org.chromium.content.browser.input.SelectPopupDialog;
import org.chromium.content.browser.input.SelectPopupDropdown;
import org.chromium.content.browser.input.SelectPopupItem;
import org.chromium.content.browser.input.SelectionEventType;
import org.chromium.content.common.ContentSwitches;
import org.chromium.content_public.browser.GestureStateListener;
import org.chromium.content_public.browser.WebContents;
import org.chromium.ui.base.DeviceFormFactor;
import org.chromium.ui.base.ViewAndroid;
import org.chromium.ui.base.ViewAndroidDelegate;
import org.chromium.ui.base.WindowAndroid;
import org.chromium.ui.gfx.DeviceDisplayInfo;

import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;

/**
 * Provides a Java-side 'wrapper' around a WebContent (native) instance.
 * Contains all the major functionality necessary to manage the lifecycle of a ContentView without
 * being tied to the view system.
 */
@JNINamespace("content")
public class ContentViewCore
        implements NavigationClient, AccessibilityStateChangeListener, ScreenOrientationObserver {

    private static final String TAG = "ContentViewCore";

    // Used to avoid enabling zooming in / out if resulting zooming will
    // produce little visible difference.
    private static final float ZOOM_CONTROLS_EPSILON = 0.007f;

    // Used to represent gestures for long press and long tap.
    private static final int IS_LONG_PRESS = 1;
    private static final int IS_LONG_TAP = 2;

    // These values are obtained from Samsung.
    // TODO(changwan): refactor SPen related code into a separate class. See
    // http://crbug.com/398169.
    private static final int SPEN_ACTION_DOWN = 211;
    private static final int SPEN_ACTION_UP = 212;
    private static final int SPEN_ACTION_MOVE = 213;
    private static final int SPEN_ACTION_CANCEL = 214;
    private static Boolean sIsSPenSupported;

    // If the embedder adds a JavaScript interface object that contains an indirect reference to
    // the ContentViewCore, then storing a strong ref to the interface object on the native
    // side would prevent garbage collection of the ContentViewCore (as that strong ref would
    // create a new GC root).
    // For that reason, we store only a weak reference to the interface object on the
    // native side. However we still need a strong reference on the Java side to
    // prevent garbage collection if the embedder doesn't maintain their own ref to the
    // interface object - the Java side ref won't create a new GC root.
    // This map stores those references. We put into the map on addJavaScriptInterface()
    // and remove from it in removeJavaScriptInterface(). The annotation class is stored for
    // the purpose of migrating injected objects from one instance of CVC to another, which
    // is used by Android WebView to support WebChromeClient.onCreateWindow scenario.
    private final Map<String, Pair<Object, Class>> mJavaScriptInterfaces =
            new HashMap<String, Pair<Object, Class>>();

    // Additionally, we keep track of all Java bound JS objects that are in use on the
    // current page to ensure that they are not garbage collected until the page is
    // navigated. This includes interface objects that have been removed
    // via the removeJavaScriptInterface API and transient objects returned from methods
    // on the interface object. Note we use HashSet rather than Set as the native side
    // expects HashSet (no bindings for interfaces).
    private final HashSet<Object> mRetainedJavaScriptObjects = new HashSet<Object>();

    /**
     * Interface that consumers of {@link ContentViewCore} must implement to allow the proper
     * dispatching of view methods through the containing view.
     *
     * <p>
     * All methods with the "super_" prefix should be routed to the parent of the
     * implementing container view.
     */
    @SuppressWarnings("javadoc")
    public interface InternalAccessDelegate {
        /**
         * @see View#drawChild(Canvas, View, long)
         */
        boolean drawChild(Canvas canvas, View child, long drawingTime);

        /**
         * @see View#onKeyUp(keyCode, KeyEvent)
         */
        boolean super_onKeyUp(int keyCode, KeyEvent event);

        /**
         * @see View#dispatchKeyEventPreIme(KeyEvent)
         */
        boolean super_dispatchKeyEventPreIme(KeyEvent event);

        /**
         * @see View#dispatchKeyEvent(KeyEvent)
         */
        boolean super_dispatchKeyEvent(KeyEvent event);

        /**
         * @see View#onGenericMotionEvent(MotionEvent)
         */
        boolean super_onGenericMotionEvent(MotionEvent event);

        /**
         * @see View#onConfigurationChanged(Configuration)
         */
        void super_onConfigurationChanged(Configuration newConfig);

        /**
         * @see View#onScrollChanged(int, int, int, int)
         */
        void onScrollChanged(int lPix, int tPix, int oldlPix, int oldtPix);

        /**
         * @see View#awakenScrollBars()
         */
        boolean awakenScrollBars();

        /**
         * @see View#awakenScrollBars(int, boolean)
         */
        boolean super_awakenScrollBars(int startDelay, boolean invalidate);
    }

    /**
     * An interface for controlling visibility and state of embedder-provided zoom controls.
     */
    public interface ZoomControlsDelegate {
        /**
         * Called when it's reasonable to show zoom controls.
         */
        void invokeZoomPicker();

        /**
         * Called when zoom controls need to be hidden (e.g. when the view hides).
         */
        void dismissZoomPicker();

        /**
         * Called when page scale has been changed, so the controls can update their state.
         */
        void updateZoomControls();
    }

    /**
     * An interface that allows the embedder to be notified when the results of
     * extractSmartClipData are available.
     */
    public interface SmartClipDataListener {
        public void onSmartClipDataExtracted(String text, String html, Rect clipRect);
    }

    /**
     * An interface that allows the embedder to be notified of navigation transition
     * related events and respond to them.
     */
    public interface NavigationTransitionDelegate {
        /**
         * Called when the navigation is deferred immediately after the response started.
         *
         * @param enteringColor The background color of the entering document, as a String
         *                      representing a legal CSS color value. This is inserted into
         *                      the transition layer's markup after the entering stylesheets
         *                      have been applied.
         */
        public void didDeferAfterResponseStarted(String enteringColor);

        /**
         * Called when a navigation transition has been detected, and we need to check
         * if it's supported.
         */
        public boolean willHandleDeferAfterResponseStarted();

        /**
         * Called when the navigation is deferred immediately after the response
         * started.
         */
        public void addEnteringStylesheetToTransition(String stylesheet);

        /**
         * Notifies that a navigation transition is started for a given frame.
         * @param frameId A positive, non-zero integer identifying the navigating frame.
         */
        public void didStartNavigationTransitionForFrame(long frameId);
    }

    private final Context mContext;
    private ViewGroup mContainerView;
    private InternalAccessDelegate mContainerViewInternals;
    private WebContents mWebContents;
    private WebContentsObserverAndroid mWebContentsObserver;

    private ContentViewClient mContentViewClient;

    private ContentSettings mContentSettings;

    // Native pointer to C++ ContentViewCoreImpl object which will be set by nativeInit().
    private long mNativeContentViewCore = 0;

    private final ObserverList<GestureStateListener> mGestureStateListeners;
    private final RewindableIterator<GestureStateListener> mGestureStateListenersIterator;
    private ZoomControlsDelegate mZoomControlsDelegate;

    private PopupZoomer mPopupZoomer;
    private SelectPopup mSelectPopup;

    private Runnable mFakeMouseMoveRunnable = null;

    // Only valid when focused on a text / password field.
    private ImeAdapter mImeAdapter;
    private ImeAdapter.AdapterInputConnectionFactory mAdapterInputConnectionFactory;
    private AdapterInputConnection mInputConnection;
    private InputMethodManagerWrapper mInputMethodManagerWrapper;

    // Lazily created paste popup menu, triggered either via long press in an
    // editable region or from tapping the insertion handle.
    private PastePopupMenu mPastePopupMenu;

    private PopupTouchHandleDrawableDelegate mTouchHandleDelegate;

    private PositionObserver mPositionObserver;

    // Size of the viewport in physical pixels as set from onSizeChanged.
    private int mViewportWidthPix;
    private int mViewportHeightPix;
    private int mPhysicalBackingWidthPix;
    private int mPhysicalBackingHeightPix;
    private int mOverdrawBottomHeightPix;
    private int mViewportSizeOffsetWidthPix;
    private int mViewportSizeOffsetHeightPix;

    // Cached copy of all positions and scales as reported by the renderer.
    private final RenderCoordinates mRenderCoordinates;

    // Tracks whether a selection is currently active.  When applied to selected text, indicates
    // whether the last selected text is still highlighted.
    private boolean mHasSelection;
    private boolean mHasInsertion;
    private String mLastSelectedText;
    private boolean mFocusedNodeEditable;
    private ActionMode mActionMode;
    private boolean mUnselectAllOnActionModeDismiss;

    // Delegate that will handle GET downloads, and be notified of completion of POST downloads.
    private ContentViewDownloadDelegate mDownloadDelegate;

    // The AccessibilityInjector that handles loading Accessibility scripts into the web page.
    private AccessibilityInjector mAccessibilityInjector;

    // Whether native accessibility, i.e. without any script injection, is allowed.
    private boolean mNativeAccessibilityAllowed;

    // Whether native accessibility, i.e. without any script injection, has been enabled.
    private boolean mNativeAccessibilityEnabled;

    // Handles native accessibility, i.e. without any script injection.
    private BrowserAccessibilityManager mBrowserAccessibilityManager;

    // System accessibility service.
    private final AccessibilityManager mAccessibilityManager;

    // Accessibility touch exploration state.
    private boolean mTouchExplorationEnabled;

    // Allows us to dynamically respond when the accessibility script injection flag changes.
    private ContentObserver mAccessibilityScriptInjectionObserver;

    // Temporary notification to tell onSizeChanged to focus a form element,
    // because the OSK was just brought up.
    private final Rect mFocusPreOSKViewportRect = new Rect();

    // On tap this will store the x, y coordinates of the touch.
    private int mLastTapX;
    private int mLastTapY;

    // Whether a touch scroll sequence is active, used to hide text selection
    // handles. Note that a scroll sequence will *always* bound a pinch
    // sequence, so this will also be true for the duration of a pinch gesture.
    private boolean mTouchScrollInProgress;

    // The outstanding fling start events that hasn't got fling end yet. It may be > 1 because
    // onNativeFlingStopped() is called asynchronously.
    private int mPotentiallyActiveFlingCount;

    private ViewAndroid mViewAndroid;

    private SmartClipDataListener mSmartClipDataListener = null;

    private NavigationTransitionDelegate mNavigationTransitionDelegate = null;

    // This holds the state of editable text (e.g. contents of <input>, contenteditable) of
    // a focused element.
    // Every time the user, IME, javascript (Blink), autofill etc. modifies the content, the new
    //  state must be reflected to this to keep consistency.
    private final Editable mEditable;

    /**
     * PID used to indicate an invalid render process.
     */
    // Keep in sync with the value returned from ContentViewCoreImpl::GetCurrentRendererProcessId()
    // if there is no render process.
    public static final int INVALID_RENDER_PROCESS_PID = 0;

    // Offsets for the events that passes through this ContentViewCore.
    private float mCurrentTouchOffsetX;
    private float mCurrentTouchOffsetY;

    // Offsets for smart clip
    private int mSmartClipOffsetX;
    private int mSmartClipOffsetY;

    // Whether the ContentViewCore requires the WebContents to be fullscreen in order to lock the
    // screen orientation.
    private boolean mFullscreenRequiredForOrientationLock = true;

    /**
     * Constructs a new ContentViewCore. Embedders must call initialize() after constructing
     * a ContentViewCore and before using it.
     *
     * @param context The context used to create this.
     */
    public ContentViewCore(Context context) {
        mContext = context;

        mAdapterInputConnectionFactory = new AdapterInputConnectionFactory();
        mInputMethodManagerWrapper = new InputMethodManagerWrapper(mContext);

        mRenderCoordinates = new RenderCoordinates();
        float deviceScaleFactor = getContext().getResources().getDisplayMetrics().density;
        String forceScaleFactor = CommandLine.getInstance().getSwitchValue(
                ContentSwitches.FORCE_DEVICE_SCALE_FACTOR);
        if (forceScaleFactor != null) {
            deviceScaleFactor = Float.valueOf(forceScaleFactor);
        }
        mRenderCoordinates.setDeviceScaleFactor(deviceScaleFactor);
        mAccessibilityManager = (AccessibilityManager)
                getContext().getSystemService(Context.ACCESSIBILITY_SERVICE);
        mGestureStateListeners = new ObserverList<GestureStateListener>();
        mGestureStateListenersIterator = mGestureStateListeners.rewindableIterator();

        mEditable = Editable.Factory.getInstance().newEditable("");
        Selection.setSelection(mEditable, 0);
    }

    /**
     * @return The context used for creating this ContentViewCore.
     */
    @CalledByNative
    public Context getContext() {
        return mContext;
    }

    /**
     * @return The ViewGroup that all view actions of this ContentViewCore should interact with.
     */
    public ViewGroup getContainerView() {
        return mContainerView;
    }

    /**
     * @return The WebContents currently being rendered.
     */
    public WebContents getWebContents() {
        return mWebContents;
    }

    /**
     * Specifies how much smaller the WebKit layout size should be relative to the size of this
     * view.
     * @param offsetXPix The X amount in pixels to shrink the viewport by.
     * @param offsetYPix The Y amount in pixels to shrink the viewport by.
     */
    public void setViewportSizeOffset(int offsetXPix, int offsetYPix) {
        if (offsetXPix != mViewportSizeOffsetWidthPix ||
                offsetYPix != mViewportSizeOffsetHeightPix) {
            mViewportSizeOffsetWidthPix = offsetXPix;
            mViewportSizeOffsetHeightPix = offsetYPix;
            if (mNativeContentViewCore != 0) nativeWasResized(mNativeContentViewCore);
        }
    }

    /**
     * Returns a delegate that can be used to add and remove views from the ContainerView.
     *
     * NOTE: Use with care, as not all ContentViewCore users setup their ContainerView in the same
     * way. In particular, the Android WebView has limitations on what implementation details can
     * be provided via a child view, as they are visible in the API and could introduce
     * compatibility breaks with existing applications. If in doubt, contact the
     * android_webview/OWNERS
     *
     * @return A ViewAndroidDelegate that can be used to add and remove views.
     */
    @VisibleForTesting
    public ViewAndroidDelegate getViewAndroidDelegate() {
        return new ViewAndroidDelegate() {
            // mContainerView can change, but this ViewAndroidDelegate can only be used to
            // add and remove views from the mContainerViewAtCreation.
            private final ViewGroup mContainerViewAtCreation = mContainerView;

            @Override
            public View acquireAnchorView() {
                View anchorView = new View(mContext);
                mContainerViewAtCreation.addView(anchorView);
                return anchorView;
            }

            @Override
            @SuppressWarnings("deprecation")  // AbsoluteLayout
            public void setAnchorViewPosition(
                    View view, float x, float y, float width, float height) {
                assert view.getParent() == mContainerViewAtCreation;

                float scale = (float) DeviceDisplayInfo.create(mContext).getDIPScale();

                // The anchor view should not go outside the bounds of the ContainerView.
                int leftMargin = Math.round(x * scale);
                int topMargin = Math.round(mRenderCoordinates.getContentOffsetYPix() + y * scale);
                int scaledWidth = Math.round(width * scale);
                // ContentViewCore currently only supports these two container view types.
                if (mContainerViewAtCreation instanceof FrameLayout) {
                    int startMargin;
                    if (ApiCompatibilityUtils.isLayoutRtl(mContainerViewAtCreation)) {
                        startMargin = mContainerViewAtCreation.getMeasuredWidth()
                                - Math.round((width + x) * scale);
                    } else {
                        startMargin = leftMargin;
                    }
                    if (scaledWidth + startMargin > mContainerViewAtCreation.getWidth()) {
                        scaledWidth = mContainerViewAtCreation.getWidth() - startMargin;
                    }
                    FrameLayout.LayoutParams lp = new FrameLayout.LayoutParams(
                        scaledWidth, Math.round(height * scale));
                    ApiCompatibilityUtils.setMarginStart(lp, startMargin);
                    lp.topMargin = topMargin;
                    view.setLayoutParams(lp);
                } else if (mContainerViewAtCreation instanceof android.widget.AbsoluteLayout) {
                    // This fixes the offset due to a difference in
                    // scrolling model of WebView vs. Chrome.
                    // TODO(sgurun) fix this to use mContainerViewAtCreation.getScroll[X/Y]()
                    // as it naturally accounts for scroll differences between
                    // these models.
                    leftMargin += mRenderCoordinates.getScrollXPixInt();
                    topMargin += mRenderCoordinates.getScrollYPixInt();

                    android.widget.AbsoluteLayout.LayoutParams lp =
                            new android.widget.AbsoluteLayout.LayoutParams(
                                scaledWidth, (int) (height * scale), leftMargin, topMargin);
                    view.setLayoutParams(lp);
                } else {
                    Log.e(TAG, "Unknown layout " + mContainerViewAtCreation.getClass().getName());
                }
            }

            @Override
            public void releaseAnchorView(View anchorView) {
                mContainerViewAtCreation.removeView(anchorView);
            }
        };
    }

    @VisibleForTesting
    public void setImeAdapterForTest(ImeAdapter imeAdapter) {
        mImeAdapter = imeAdapter;
    }

    @VisibleForTesting
    public ImeAdapter getImeAdapterForTest() {
        return mImeAdapter;
    }

    @VisibleForTesting
    public void setAdapterInputConnectionFactory(AdapterInputConnectionFactory factory) {
        mAdapterInputConnectionFactory = factory;
    }

    @VisibleForTesting
    public void setInputMethodManagerWrapperForTest(InputMethodManagerWrapper immw) {
        mInputMethodManagerWrapper = immw;
    }

    @VisibleForTesting
    public AdapterInputConnection getInputConnectionForTest() {
        return mInputConnection;
    }

    private ImeAdapter createImeAdapter(Context context) {
        return new ImeAdapter(mInputMethodManagerWrapper,
                new ImeAdapter.ImeAdapterDelegate() {
                    @Override
                    public void onImeEvent() {
                        if (mPopupZoomer.isShowing()) {
                            mPopupZoomer.hide(true);
                        }
                        getContentViewClient().onImeEvent();
                        hideTextHandles();
                    }

                    @Override
                    public void onDismissInput() {
                        getContentViewClient().onImeStateChangeRequested(false);
                    }

                    @Override
                    public View getAttachedView() {
                        return mContainerView;
                    }

                    @Override
                    public ResultReceiver getNewShowKeyboardReceiver() {
                        return new ResultReceiver(new Handler()) {
                            @Override
                            public void onReceiveResult(int resultCode, Bundle resultData) {
                                getContentViewClient().onImeStateChangeRequested(
                                        resultCode == InputMethodManager.RESULT_SHOWN ||
                                        resultCode == InputMethodManager.RESULT_UNCHANGED_SHOWN);
                                if (resultCode == InputMethodManager.RESULT_SHOWN) {
                                    // If OSK is newly shown, delay the form focus until
                                    // the onSizeChanged (in order to adjust relative to the
                                    // new size).
                                    // TODO(jdduke): We should not assume that onSizeChanged will
                                    // always be called, crbug.com/294908.
                                    getContainerView().getWindowVisibleDisplayFrame(
                                            mFocusPreOSKViewportRect);
                                } else if (hasFocus() && resultCode ==
                                        InputMethodManager.RESULT_UNCHANGED_SHOWN) {
                                    // If the OSK was already there, focus the form immediately.
                                    scrollFocusedEditableNodeIntoView();
                                }
                            }
                        };
                    }
                }
        );
    }

    /**
     *
     * @param containerView The view that will act as a container for all views created by this.
     * @param internalDispatcher Handles dispatching all hidden or super methods to the
     *                           containerView.
     * @param nativeWebContents A pointer to the native web contents.
     * @param windowAndroid An instance of the WindowAndroid.
     */
    // Perform important post-construction set up of the ContentViewCore.
    // We do not require the containing view in the constructor to allow embedders to create a
    // ContentViewCore without having fully created its containing view. The containing view
    // is a vital component of the ContentViewCore, so embedders must exercise caution in what
    // they do with the ContentViewCore before calling initialize().
    // We supply the nativeWebContents pointer here rather than in the constructor to allow us
    // to set the private browsing mode at a later point for the WebView implementation.
    // Note that the caller remains the owner of the nativeWebContents and is responsible for
    // deleting it after destroying the ContentViewCore.
    public void initialize(ViewGroup containerView, InternalAccessDelegate internalDispatcher,
            long nativeWebContents, WindowAndroid windowAndroid) {
        setContainerView(containerView);

        long windowNativePointer = windowAndroid.getNativePointer();
        assert windowNativePointer != 0;
        mViewAndroid = new ViewAndroid(windowAndroid, getViewAndroidDelegate());
        long viewAndroidNativePointer = mViewAndroid.getNativePointer();
        assert viewAndroidNativePointer != 0;

        mZoomControlsDelegate = new ZoomControlsDelegate() {
            @Override
            public void invokeZoomPicker() {}
            @Override
            public void dismissZoomPicker() {}
            @Override
            public void updateZoomControls() {}
        };

        mNativeContentViewCore = nativeInit(
                nativeWebContents, viewAndroidNativePointer, windowNativePointer,
                mRetainedJavaScriptObjects);
        mWebContents = nativeGetWebContentsAndroid(mNativeContentViewCore);
        mContentSettings = new ContentSettings(this, mNativeContentViewCore);

        setContainerViewInternals(internalDispatcher);
        mRenderCoordinates.reset();
        initPopupZoomer(mContext);
        mImeAdapter = createImeAdapter(mContext);

        mAccessibilityInjector = AccessibilityInjector.newInstance(this);

        mWebContentsObserver = new WebContentsObserverAndroid(mWebContents) {
            @Override
            public void didNavigateMainFrame(String url, String baseUrl,
                    boolean isNavigationToDifferentPage, boolean isFragmentNavigation) {
                if (!isNavigationToDifferentPage) return;
                hidePopups();
                resetScrollInProgress();
                resetGestureDetection();
            }

            @Override
            public void renderProcessGone(boolean wasOomProtected) {
                hidePopups();
                resetScrollInProgress();
                // No need to reset gesture detection as the detector will have
                // been destroyed in the RenderWidgetHostView.
            }
        };
    }

    /**
     * Sets a new container view for this {@link ContentViewCore}.
     *
     * <p>WARNING: This is not a general purpose method and has been designed with WebView
     * fullscreen in mind. Please be aware that it might not be appropriate for other use cases
     * and that it has a number of limitations. For example the PopupZoomer only works with the
     * container view with which this ContentViewCore has been initialized.
     *
     * <p>This method only performs a small part of replacing the container view and
     * embedders are responsible for:
     * <ul>
     *     <li>Disconnecting the old container view from this ContentViewCore</li>
     *     <li>Updating the InternalAccessDelegate</li>
     *     <li>Reconciling the state of this ContentViewCore with the new container view</li>
     *     <li>Tearing down and recreating the native GL rendering where appropriate</li>
     *     <li>etc.</li>
     * </ul>
     */
    public void setContainerView(ViewGroup containerView) {
        TraceEvent.begin();
        if (mContainerView != null) {
            mPastePopupMenu = null;
            mInputConnection = null;
            hidePopups();
        }

        mContainerView = containerView;
        mPositionObserver = new ViewPositionObserver(mContainerView);
        String contentDescription = "Web View";
        if (R.string.accessibility_content_view == 0) {
            Log.w(TAG, "Setting contentDescription to 'Web View' as no value was specified.");
        } else {
            contentDescription = mContext.getResources().getString(
                    R.string.accessibility_content_view);
        }
        mContainerView.setContentDescription(contentDescription);
        mContainerView.setWillNotDraw(false);
        mContainerView.setClickable(true);
        TraceEvent.end();
    }

    @CalledByNative
    void onNativeContentViewCoreDestroyed(long nativeContentViewCore) {
        assert nativeContentViewCore == mNativeContentViewCore;
        mNativeContentViewCore = 0;
    }

    /**
     * Set the Container view Internals.
     * @param internalDispatcher Handles dispatching all hidden or super methods to the
     *                           containerView.
     */
    public void setContainerViewInternals(InternalAccessDelegate internalDispatcher) {
        mContainerViewInternals = internalDispatcher;
    }

    private void initPopupZoomer(Context context) {
        mPopupZoomer = new PopupZoomer(context);
        mPopupZoomer.setOnVisibilityChangedListener(new PopupZoomer.OnVisibilityChangedListener() {
            // mContainerView can change, but this OnVisibilityChangedListener can only be used
            // to add and remove views from the mContainerViewAtCreation.
            private final ViewGroup mContainerViewAtCreation = mContainerView;

            @Override
            public void onPopupZoomerShown(final PopupZoomer zoomer) {
                mContainerViewAtCreation.post(new Runnable() {
                    @Override
                    public void run() {
                        if (mContainerViewAtCreation.indexOfChild(zoomer) == -1) {
                            mContainerViewAtCreation.addView(zoomer);
                        } else {
                            assert false : "PopupZoomer should never be shown without being hidden";
                        }
                    }
                });
            }

            @Override
            public void onPopupZoomerHidden(final PopupZoomer zoomer) {
                mContainerViewAtCreation.post(new Runnable() {
                    @Override
                    public void run() {
                        if (mContainerViewAtCreation.indexOfChild(zoomer) != -1) {
                            mContainerViewAtCreation.removeView(zoomer);
                            mContainerViewAtCreation.invalidate();
                        } else {
                            assert false : "PopupZoomer should never be hidden without being shown";
                        }
                    }
                });
            }
        });
        // TODO(yongsheng): LONG_TAP is not enabled in PopupZoomer. So need to dispatch a LONG_TAP
        // gesture if a user completes a tap on PopupZoomer UI after a LONG_PRESS gesture.
        PopupZoomer.OnTapListener listener = new PopupZoomer.OnTapListener() {
            // mContainerView can change, but this OnTapListener can only be used
            // with the mContainerViewAtCreation.
            private final ViewGroup mContainerViewAtCreation = mContainerView;

            @Override
            public boolean onSingleTap(View v, MotionEvent e) {
                mContainerViewAtCreation.requestFocus();
                if (mNativeContentViewCore != 0) {
                    nativeSingleTap(mNativeContentViewCore, e.getEventTime(), e.getX(), e.getY());
                }
                return true;
            }

            @Override
            public boolean onLongPress(View v, MotionEvent e) {
                if (mNativeContentViewCore != 0) {
                    nativeLongPress(mNativeContentViewCore, e.getEventTime(), e.getX(), e.getY());
                }
                return true;
            }
        };
        mPopupZoomer.setOnTapListener(listener);
    }

    /**
     * Destroy the internal state of the ContentView. This method may only be
     * called after the ContentView has been removed from the view system. No
     * other methods may be called on this ContentView after this method has
     * been called.
     */
    public void destroy() {
        if (mNativeContentViewCore != 0) {
            nativeOnJavaContentViewCoreDestroyed(mNativeContentViewCore);
        }
        mWebContents = null;
        if (mViewAndroid != null) mViewAndroid.destroy();
        mNativeContentViewCore = 0;
        mContentSettings = null;
        mJavaScriptInterfaces.clear();
        mRetainedJavaScriptObjects.clear();
        unregisterAccessibilityContentObserver();
        mGestureStateListeners.clear();
        ScreenOrientationListener.getInstance().removeObserver(this);
        mPositionObserver.clearListener();
    }

    private void unregisterAccessibilityContentObserver() {
        if (mAccessibilityScriptInjectionObserver == null) {
            return;
        }
        getContext().getContentResolver().unregisterContentObserver(
                mAccessibilityScriptInjectionObserver);
        mAccessibilityScriptInjectionObserver = null;
    }

    /**
     * Returns true initially, false after destroy() has been called.
     * It is illegal to call any other public method after destroy().
     */
    public boolean isAlive() {
        return mNativeContentViewCore != 0;
    }

    /**
     * This is only useful for passing over JNI to native code that requires ContentViewCore*.
     * @return native ContentViewCore pointer.
     */
    @CalledByNative
    public long getNativeContentViewCore() {
        return mNativeContentViewCore;
    }

    public void setContentViewClient(ContentViewClient client) {
        if (client == null) {
            throw new IllegalArgumentException("The client can't be null.");
        }
        mContentViewClient = client;
    }

    @VisibleForTesting
    public ContentViewClient getContentViewClient() {
        if (mContentViewClient == null) {
            // We use the Null Object pattern to avoid having to perform a null check in this class.
            // We create it lazily because most of the time a client will be set almost immediately
            // after ContentView is created.
            mContentViewClient = new ContentViewClient();
            // We don't set the native ContentViewClient pointer here on purpose. The native
            // implementation doesn't mind a null delegate and using one is better than passing a
            // Null Object, since we cut down on the number of JNI calls.
        }
        return mContentViewClient;
    }

    public int getBackgroundColor() {
        assert mWebContents != null;
        return mWebContents.getBackgroundColor();
    }

    @CalledByNative
    private void onBackgroundColorChanged(int color) {
        getContentViewClient().onBackgroundColorChanged(color);
    }

    /**
     * Load url without fixing up the url string. Consumers of ContentView are responsible for
     * ensuring the URL passed in is properly formatted (i.e. the scheme has been added if left
     * off during user input).
     *
     * @param params Parameters for this load.
     */
    public void loadUrl(LoadUrlParams params) {
        if (mNativeContentViewCore == 0) return;

        nativeLoadUrl(mNativeContentViewCore,
                params.mUrl,
                params.mLoadUrlType,
                params.mTransitionType,
                params.getReferrer() != null ? params.getReferrer().getUrl() : null,
                params.getReferrer() != null ? params.getReferrer().getPolicy() : 0,
                params.mUaOverrideOption,
                params.getExtraHeadersString(),
                params.mPostData,
                params.mBaseUrlForDataUrl,
                params.mVirtualUrlForDataUrl,
                params.mCanLoadLocalResources,
                params.mIsRendererInitiated);
    }

    /**
     * Stops loading the current web contents.
     */
    public void stopLoading() {
        if (mWebContents != null) mWebContents.stop();
    }

    /**
     * Get the URL of the current page.
     *
     * @return The URL of the current page.
     */
    public String getUrl() {
        if (mNativeContentViewCore != 0) return nativeGetURL(mNativeContentViewCore);
        return null;
    }

    /**
     * Get the title of the current page.
     *
     * @return The title of the current page.
     */
    public String getTitle() {
        return mWebContents == null ? null : mWebContents.getTitle();
    }

    /**
     * Shows an interstitial page driven by the passed in delegate.
     *
     * @param url The URL being blocked by the interstitial.
     * @param delegate The delegate handling the interstitial.
     */
    @VisibleForTesting
    public void showInterstitialPage(
            String url, InterstitialPageDelegateAndroid delegate) {
        assert mWebContents != null;
        mWebContents.showInterstitialPage(url, delegate.getNative());
    }

    /**
     * @return Whether the page is currently showing an interstitial, such as a bad HTTPS page.
     */
    public boolean isShowingInterstitialPage() {
        assert mWebContents != null;
        return mWebContents.isShowingInterstitialPage();
    }

    /**
     * @return Viewport width in physical pixels as set from onSizeChanged.
     */
    @CalledByNative
    public int getViewportWidthPix() { return mViewportWidthPix; }

    /**
     * @return Viewport height in physical pixels as set from onSizeChanged.
     */
    @CalledByNative
    public int getViewportHeightPix() { return mViewportHeightPix; }

    /**
     * @return Width of underlying physical surface.
     */
    @CalledByNative
    public int getPhysicalBackingWidthPix() { return mPhysicalBackingWidthPix; }

    /**
     * @return Height of underlying physical surface.
     */
    @CalledByNative
    public int getPhysicalBackingHeightPix() { return mPhysicalBackingHeightPix; }

    /**
     * @return Amount the output surface extends past the bottom of the window viewport.
     */
    @CalledByNative
    public int getOverdrawBottomHeightPix() { return mOverdrawBottomHeightPix; }

    /**
     * @return The amount to shrink the viewport relative to {@link #getViewportWidthPix()}.
     */
    @CalledByNative
    public int getViewportSizeOffsetWidthPix() { return mViewportSizeOffsetWidthPix; }

    /**
     * @return The amount to shrink the viewport relative to {@link #getViewportHeightPix()}.
     */
    @CalledByNative
    public int getViewportSizeOffsetHeightPix() { return mViewportSizeOffsetHeightPix; }

    /**
     * @see android.webkit.WebView#getContentHeight()
     */
    public float getContentHeightCss() {
        return mRenderCoordinates.getContentHeightCss();
    }

    /**
     * @see android.webkit.WebView#getContentWidth()
     */
    public float getContentWidthCss() {
        return mRenderCoordinates.getContentWidthCss();
    }

    // TODO(teddchoc): Remove all these navigation controller methods from here and have the
    //                 embedders manage it.
    /**
     * @return Whether the current WebContents has a previous navigation entry.
     */
    public boolean canGoBack() {
        return mWebContents != null && mWebContents.getNavigationController().canGoBack();
    }

    /**
     * @return Whether the current WebContents has a navigation entry after the current one.
     */
    public boolean canGoForward() {
        return mWebContents != null && mWebContents.getNavigationController().canGoForward();
    }

    /**
     * @param offset The offset into the navigation history.
     * @return Whether we can move in history by given offset
     */
    public boolean canGoToOffset(int offset) {
        return mWebContents != null &&
                mWebContents.getNavigationController().canGoToOffset(offset);
    }

    /**
     * Navigates to the specified offset from the "current entry". Does nothing if the offset is out
     * of bounds.
     * @param offset The offset into the navigation history.
     */
    public void goToOffset(int offset) {
        if (mWebContents != null) mWebContents.getNavigationController().goToOffset(offset);
    }

    @Override
    public void goToNavigationIndex(int index) {
        if (mWebContents != null) {
            mWebContents.getNavigationController().goToNavigationIndex(index);
        }
    }

    /**
     * Goes to the navigation entry before the current one.
     */
    public void goBack() {
        if (mWebContents != null) mWebContents.getNavigationController().goBack();
    }

    /**
     * Goes to the navigation entry following the current one.
     */
    public void goForward() {
        if (mWebContents != null) mWebContents.getNavigationController().goForward();
    }

    /**
     * Loads the current navigation if there is a pending lazy load (after tab restore).
     */
    public void loadIfNecessary() {
        if (mWebContents != null) mWebContents.getNavigationController().loadIfNecessary();
    }

    /**
     * Requests the current navigation to be loaded upon the next call to loadIfNecessary().
     */
    public void requestRestoreLoad() {
        if (mWebContents != null) mWebContents.getNavigationController().requestRestoreLoad();
    }

    /**
     * Reload the current page.
     */
    public void reload(boolean checkForRepost) {
        mAccessibilityInjector.addOrRemoveAccessibilityApisIfNecessary();
        if (mWebContents != null) mWebContents.getNavigationController().reload(checkForRepost);
    }

    /**
     * Reload the current page, ignoring the contents of the cache.
     */
    public void reloadIgnoringCache(boolean checkForRepost) {
        mAccessibilityInjector.addOrRemoveAccessibilityApisIfNecessary();
        if (mWebContents != null) mWebContents.getNavigationController().reloadIgnoringCache(
                checkForRepost);
    }

    /**
     * Cancel the pending reload.
     */
    public void cancelPendingReload() {
        if (mWebContents != null) mWebContents.getNavigationController().cancelPendingReload();
    }

    /**
     * Continue the pending reload.
     */
    public void continuePendingReload() {
        if (mWebContents != null) mWebContents.getNavigationController().continuePendingReload();
    }

    /**
     * Clears the ContentViewCore's page history in both the backwards and
     * forwards directions.
     */
    public void clearHistory() {
        if (mNativeContentViewCore != 0) nativeClearHistory(mNativeContentViewCore);
    }

    /**
     * @return The selected text (empty if no text selected).
     */
    public String getSelectedText() {
        return mHasSelection ? mLastSelectedText : "";
    }

    /**
     * @return Whether the current selection is editable (false if no text selected).
     */
    public boolean isSelectionEditable() {
        return mHasSelection ? mFocusedNodeEditable : false;
    }

    /**
     * @return Whether the current focused node is editable.
     */
    public boolean isFocusedNodeEditable() {
        return mFocusedNodeEditable;
    }

    // End FrameLayout overrides.

    /**
     * TODO(changwan): refactor SPen related code into a separate class. See
     * http://crbug.com/398169.
     * @return Whether SPen is supported on the device.
     */
    public static boolean isSPenSupported(Context context) {
        if (sIsSPenSupported == null)
            sIsSPenSupported = detectSPenSupport(context);
        return sIsSPenSupported.booleanValue();
    }

    private static boolean detectSPenSupport(Context context) {
        if (!"SAMSUNG".equalsIgnoreCase(Build.MANUFACTURER))
            return false;

        final FeatureInfo[] infos = context.getPackageManager().getSystemAvailableFeatures();
        for (FeatureInfo info : infos) {
            if ("com.sec.feature.spen_usp".equalsIgnoreCase(info.name)) {
                return true;
            }
        }
        return false;
    }

    /**
     * Convert SPen event action into normal event action.
     * TODO(changwan): refactor SPen related code into a separate class. See
     * http://crbug.com/398169.
     *
     * @param eventActionMasked Input event action. It is assumed that it is masked as the values
                                cannot be ORed.
     * @return Event action after the conversion
     */
    public static int convertSPenEventAction(int eventActionMasked) {
        // S-Pen support: convert to normal stylus event handling
        switch (eventActionMasked) {
            case SPEN_ACTION_DOWN:
                return MotionEvent.ACTION_DOWN;
            case SPEN_ACTION_UP:
                return MotionEvent.ACTION_UP;
            case SPEN_ACTION_MOVE:
                return MotionEvent.ACTION_MOVE;
            case SPEN_ACTION_CANCEL:
                return MotionEvent.ACTION_CANCEL;
            default:
                return eventActionMasked;
        }
    }

    /**
     * @see View#onTouchEvent(MotionEvent)
     */
    public boolean onTouchEvent(MotionEvent event) {
        final boolean isTouchHandleEvent = false;
        return onTouchEventImpl(event, isTouchHandleEvent);
    }

    private boolean onTouchEventImpl(MotionEvent event, boolean isTouchHandleEvent) {
        TraceEvent.begin("onTouchEvent");
        try {
            int eventAction = event.getActionMasked();

            if (eventAction == MotionEvent.ACTION_DOWN) {
                cancelRequestToScrollFocusedEditableNodeIntoView();
            }

            if (isSPenSupported(mContext))
                eventAction = convertSPenEventAction(eventAction);
            if (!isValidTouchEventActionForNative(eventAction)) return false;

            if (mNativeContentViewCore == 0) return false;

            // A zero offset is quite common, in which case the unnecessary copy should be avoided.
            MotionEvent offset = null;
            if (mCurrentTouchOffsetX != 0 || mCurrentTouchOffsetY != 0) {
                offset = createOffsetMotionEvent(event);
                event = offset;
            }

            final int pointerCount = event.getPointerCount();
            final boolean consumed = nativeOnTouchEvent(mNativeContentViewCore, event,
                    event.getEventTime(), eventAction,
                    pointerCount, event.getHistorySize(), event.getActionIndex(),
                    event.getX(), event.getY(),
                    pointerCount > 1 ? event.getX(1) : 0,
                    pointerCount > 1 ? event.getY(1) : 0,
                    event.getPointerId(0), pointerCount > 1 ? event.getPointerId(1) : -1,
                    event.getTouchMajor(), pointerCount > 1 ? event.getTouchMajor(1) : 0,
                    event.getRawX(), event.getRawY(),
                    event.getToolType(0),
                    pointerCount > 1 ? event.getToolType(1) : MotionEvent.TOOL_TYPE_UNKNOWN,
                    event.getButtonState(),
                    isTouchHandleEvent);

            if (offset != null) offset.recycle();
            return consumed;
        } finally {
            TraceEvent.end("onTouchEvent");
        }
    }

    private static boolean isValidTouchEventActionForNative(int eventAction) {
        // Only these actions have any effect on gesture detection.  Other
        // actions have no corresponding WebTouchEvent type and may confuse the
        // touch pipline, so we ignore them entirely.
        return eventAction == MotionEvent.ACTION_DOWN
                || eventAction == MotionEvent.ACTION_UP
                || eventAction == MotionEvent.ACTION_CANCEL
                || eventAction == MotionEvent.ACTION_MOVE
                || eventAction == MotionEvent.ACTION_POINTER_DOWN
                || eventAction == MotionEvent.ACTION_POINTER_UP;
    }

    public void setIgnoreRemainingTouchEvents() {
        resetGestureDetection();
    }

    public boolean isScrollInProgress() {
        return mTouchScrollInProgress || mPotentiallyActiveFlingCount > 0;
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void onFlingStartEventConsumed(int vx, int vy) {
        mTouchScrollInProgress = false;
        mPotentiallyActiveFlingCount++;
        for (mGestureStateListenersIterator.rewind();
                    mGestureStateListenersIterator.hasNext();) {
            mGestureStateListenersIterator.next().onFlingStartGesture(
                    vx, vy, computeVerticalScrollOffset(), computeVerticalScrollExtent());
        }
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void onFlingStartEventHadNoConsumer(int vx, int vy) {
        mTouchScrollInProgress = false;
        for (mGestureStateListenersIterator.rewind();
                    mGestureStateListenersIterator.hasNext();) {
            mGestureStateListenersIterator.next().onUnhandledFlingStartEvent(vx, vy);
        }
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void onFlingCancelEventAck() {
        updateGestureStateListener(GestureEventType.FLING_CANCEL);
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void onScrollBeginEventAck() {
        mTouchScrollInProgress = true;
        hidePastePopup();
        mZoomControlsDelegate.invokeZoomPicker();
        updateGestureStateListener(GestureEventType.SCROLL_START);
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void onScrollUpdateGestureConsumed() {
        mZoomControlsDelegate.invokeZoomPicker();
        for (mGestureStateListenersIterator.rewind();
                mGestureStateListenersIterator.hasNext();) {
            mGestureStateListenersIterator.next().onScrollUpdateGestureConsumed();
        }
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void onScrollEndEventAck() {
        if (!mTouchScrollInProgress) return;
        mTouchScrollInProgress = false;
        updateGestureStateListener(GestureEventType.SCROLL_END);
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void onPinchBeginEventAck() {
        updateGestureStateListener(GestureEventType.PINCH_BEGIN);
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void onPinchEndEventAck() {
        updateGestureStateListener(GestureEventType.PINCH_END);
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void onSingleTapEventAck(boolean consumed, int x, int y) {
        for (mGestureStateListenersIterator.rewind();
                mGestureStateListenersIterator.hasNext();) {
            mGestureStateListenersIterator.next().onSingleTap(consumed, x, y);
        }
    }

    /**
     * Called just prior to a tap or press gesture being forwarded to the renderer.
     */
    @SuppressWarnings("unused")
    @CalledByNative
    private boolean filterTapOrPressEvent(int type, int x, int y) {
        if (type == GestureEventType.LONG_PRESS && offerLongPressToEmbedder()) {
            return true;
        }
        updateForTapOrPress(type, x, y);
        return false;
    }

    @VisibleForTesting
    public void sendDoubleTapForTest(long timeMs, int x, int y) {
        if (mNativeContentViewCore == 0) return;
        nativeDoubleTap(mNativeContentViewCore, timeMs, x, y);
    }

    @VisibleForTesting
    public void flingForTest(long timeMs, int x, int y, int velocityX, int velocityY) {
        if (mNativeContentViewCore == 0) return;
        nativeFlingCancel(mNativeContentViewCore, timeMs);
        nativeScrollBegin(mNativeContentViewCore, timeMs, x, y, velocityX, velocityY);
        nativeFlingStart(mNativeContentViewCore, timeMs, x, y, velocityX, velocityY);
    }

    /**
     * Cancel any fling gestures active.
     * @param timeMs Current time (in milliseconds).
     */
    public void cancelFling(long timeMs) {
        if (mNativeContentViewCore == 0) return;
        nativeFlingCancel(mNativeContentViewCore, timeMs);
    }

    /**
     * Add a listener that gets alerted on gesture state changes.
     * @param listener Listener to add.
     */
    public void addGestureStateListener(GestureStateListener listener) {
        mGestureStateListeners.addObserver(listener);
    }

    /**
     * Removes a listener that was added to watch for gesture state changes.
     * @param listener Listener to remove.
     */
    public void removeGestureStateListener(GestureStateListener listener) {
        mGestureStateListeners.removeObserver(listener);
    }

    void updateGestureStateListener(int gestureType) {
        for (mGestureStateListenersIterator.rewind();
                mGestureStateListenersIterator.hasNext();) {
            GestureStateListener listener = mGestureStateListenersIterator.next();
            switch (gestureType) {
                case GestureEventType.PINCH_BEGIN:
                    listener.onPinchStarted();
                    break;
                case GestureEventType.PINCH_END:
                    listener.onPinchEnded();
                    break;
                case GestureEventType.FLING_END:
                    listener.onFlingEndGesture(
                            computeVerticalScrollOffset(),
                            computeVerticalScrollExtent());
                    break;
                case GestureEventType.FLING_CANCEL:
                    listener.onFlingCancelGesture();
                    break;
                case GestureEventType.SCROLL_START:
                    listener.onScrollStarted(
                            computeVerticalScrollOffset(),
                            computeVerticalScrollExtent());
                    break;
                case GestureEventType.SCROLL_END:
                    listener.onScrollEnded(
                            computeVerticalScrollOffset(),
                            computeVerticalScrollExtent());
                    break;
                default:
                    break;
            }
        }
    }

    /**
     * Requests the renderer insert a link to the specified stylesheet in the
     * main frame's document.
     */
    void addStyleSheetByURL(String url) {
        assert mWebContents != null;
        mWebContents.addStyleSheetByURL(url);
    }

    /** Callback interface for evaluateJavaScript(). */
    public interface JavaScriptCallback {
        void handleJavaScriptResult(String jsonResult);
    }

    /**
     * Injects the passed Javascript code in the current page and evaluates it.
     * If a result is required, pass in a callback.
     * Used in automation tests.
     *
     * @param script The Javascript to execute.
     * @param callback The callback to be fired off when a result is ready. The script's
     *                 result will be json encoded and passed as the parameter, and the call
     *                 will be made on the main thread.
     *                 If no result is required, pass null.
     */
    public void evaluateJavaScript(String script, JavaScriptCallback callback) {
        if (mNativeContentViewCore == 0) return;
        nativeEvaluateJavaScript(mNativeContentViewCore, script, callback, false);
    }

    /**
     * Injects the passed Javascript code in the current page and evaluates it.
     * If there is no page existing, a new one will be created.
     *
     * @param script The Javascript to execute.
     */
    public void evaluateJavaScriptEvenIfNotYetNavigated(String script) {
        if (mNativeContentViewCore == 0) return;
        nativeEvaluateJavaScript(mNativeContentViewCore, script, null, true);
    }

    /**
     * Post a message to a frame.
     * TODO(sgurun) also add support for transferring a message channel port.
     *
     * @param frameName The name of the frame. If the name is null the message is posted
     *                  to the main frame.
     * @param message   The message
     * @param sourceOrigin  The source origin
     * @param targetOrigin  The target origin
     */
    public void postMessageToFrame(String frameName, String message,
            String sourceOrigin, String targetOrigin) {
        if (mNativeContentViewCore == 0) return;
        nativePostMessageToFrame(mNativeContentViewCore, frameName, message, sourceOrigin,
            targetOrigin);
    }

    /**
     * To be called when the ContentView is shown.
     */
    public void onShow() {
        assert mWebContents != null;
        mWebContents.onShow();
        setAccessibilityState(mAccessibilityManager.isEnabled());
    }

    /**
     * @return The ID of the renderer process that backs this tab or
     *         {@link #INVALID_RENDER_PROCESS_PID} if there is none.
     */
    public int getCurrentRenderProcessId() {
        return nativeGetCurrentRenderProcessId(mNativeContentViewCore);
    }

    /**
     * To be called when the ContentView is hidden.
     */
    public void onHide() {
        assert mWebContents != null;
        hidePopups();
        setInjectedAccessibility(false);
        mWebContents.onHide();
    }

    /**
     * Return the ContentSettings object used to retrieve the settings for this
     * ContentViewCore. For modifications, ChromeNativePreferences is to be used.
     * @return A ContentSettings object that can be used to retrieve this
     *         ContentViewCore's settings.
     */
    public ContentSettings getContentSettings() {
        return mContentSettings;
    }

    private void hidePopups() {
        mUnselectAllOnActionModeDismiss = true;
        hideSelectActionBar();
        hidePastePopup();
        hideSelectPopup();
        hideTextHandles();
    }

    public void hideSelectActionBar() {
        if (mActionMode != null) {
            mActionMode.finish();
            mActionMode = null;
        }
    }

    public boolean isSelectActionBarShowing() {
        return mActionMode != null;
    }

    private void resetGestureDetection() {
        if (mNativeContentViewCore == 0) return;
        nativeResetGestureDetection(mNativeContentViewCore);
    }

    /**
     * @see View#onAttachedToWindow()
     */
    @SuppressWarnings("javadoc")
    public void onAttachedToWindow() {
        setAccessibilityState(mAccessibilityManager.isEnabled());

        ScreenOrientationListener.getInstance().addObserver(this, mContext);
        GamepadList.onAttachedToWindow(mContext);
    }

    /**
     * @see View#onDetachedFromWindow()
     */
    @SuppressWarnings("javadoc")
    @SuppressLint("MissingSuperCall")
    public void onDetachedFromWindow() {
        setInjectedAccessibility(false);
        hidePopups();
        mZoomControlsDelegate.dismissZoomPicker();
        unregisterAccessibilityContentObserver();

        ScreenOrientationListener.getInstance().removeObserver(this);
        GamepadList.onDetachedFromWindow();
    }

    /**
     * @see View#onVisibilityChanged(android.view.View, int)
     */
    public void onVisibilityChanged(View changedView, int visibility) {
        if (visibility != View.VISIBLE) {
            mZoomControlsDelegate.dismissZoomPicker();
        }
    }

    /**
     * @see View#onCreateInputConnection(EditorInfo)
     */
    public InputConnection onCreateInputConnection(EditorInfo outAttrs) {
        if (!mImeAdapter.hasTextInputType()) {
            // Although onCheckIsTextEditor will return false in this case, the EditorInfo
            // is still used by the InputMethodService. Need to make sure the IME doesn't
            // enter fullscreen mode.
            outAttrs.imeOptions = EditorInfo.IME_FLAG_NO_FULLSCREEN;
        }
        mInputConnection = mAdapterInputConnectionFactory.get(mContainerView, mImeAdapter,
                mEditable, outAttrs);
        return mInputConnection;
    }

    @VisibleForTesting
    public AdapterInputConnection getAdapterInputConnectionForTest() {
        return mInputConnection;
    }

    @VisibleForTesting
    public Editable getEditableForTest() {
        return mEditable;
    }

    /**
     * @see View#onCheckIsTextEditor()
     */
    public boolean onCheckIsTextEditor() {
        return mImeAdapter.hasTextInputType();
    }

    /**
     * @see View#onConfigurationChanged(Configuration)
     */
    @SuppressWarnings("javadoc")
    public void onConfigurationChanged(Configuration newConfig) {
        TraceEvent.begin();

        if (newConfig.keyboard != Configuration.KEYBOARD_NOKEYS) {
            if (mNativeContentViewCore != 0) {
                mImeAdapter.attach(nativeGetNativeImeAdapter(mNativeContentViewCore),
                        ImeAdapter.getTextInputTypeNone());
            }
            mInputMethodManagerWrapper.restartInput(mContainerView);
        }
        mContainerViewInternals.super_onConfigurationChanged(newConfig);

        // To request layout has side effect, but it seems OK as it only happen in
        // onConfigurationChange and layout has to be changed in most case.
        mContainerView.requestLayout();
        TraceEvent.end();
    }

    /**
     * @see View#onSizeChanged(int, int, int, int)
     */
    @SuppressWarnings("javadoc")
    public void onSizeChanged(int wPix, int hPix, int owPix, int ohPix) {
        if (getViewportWidthPix() == wPix && getViewportHeightPix() == hPix) return;

        mViewportWidthPix = wPix;
        mViewportHeightPix = hPix;
        if (mNativeContentViewCore != 0) {
            nativeWasResized(mNativeContentViewCore);
        }

        updateAfterSizeChanged();
    }

    /**
     * Called when the underlying surface the compositor draws to changes size.
     * This may be larger than the viewport size.
     */
    public void onPhysicalBackingSizeChanged(int wPix, int hPix) {
        if (mPhysicalBackingWidthPix == wPix && mPhysicalBackingHeightPix == hPix) return;

        mPhysicalBackingWidthPix = wPix;
        mPhysicalBackingHeightPix = hPix;

        if (mNativeContentViewCore != 0) {
            nativeWasResized(mNativeContentViewCore);
        }
    }

    /**
     * Called when the amount the surface is overdrawing off the bottom has changed.
     * @param overdrawHeightPix The overdraw height.
     */
    public void onOverdrawBottomHeightChanged(int overdrawHeightPix) {
        if (mOverdrawBottomHeightPix == overdrawHeightPix) return;

        mOverdrawBottomHeightPix = overdrawHeightPix;

        if (mNativeContentViewCore != 0) {
            nativeWasResized(mNativeContentViewCore);
        }
    }

    private void updateAfterSizeChanged() {
        mPopupZoomer.hide(false);

        // Execute a delayed form focus operation because the OSK was brought
        // up earlier.
        if (!mFocusPreOSKViewportRect.isEmpty()) {
            Rect rect = new Rect();
            getContainerView().getWindowVisibleDisplayFrame(rect);
            if (!rect.equals(mFocusPreOSKViewportRect)) {
                // Only assume the OSK triggered the onSizeChanged if width was preserved.
                if (rect.width() == mFocusPreOSKViewportRect.width()) {
                    scrollFocusedEditableNodeIntoView();
                }
                cancelRequestToScrollFocusedEditableNodeIntoView();
            }
        }
    }

    private void cancelRequestToScrollFocusedEditableNodeIntoView() {
        // Zero-ing the rect will prevent |updateAfterSizeChanged()| from
        // issuing the delayed form focus event.
        mFocusPreOSKViewportRect.setEmpty();
    }

    private void scrollFocusedEditableNodeIntoView() {
        assert mWebContents != null;
        mWebContents.scrollFocusedEditableNodeIntoView();
    }

    /**
     * Selects the word around the caret, if any.
     * The caller can check if selection actually occurred by listening to OnSelectionChanged.
     */
    public void selectWordAroundCaret() {
        assert mWebContents != null;
        mWebContents.selectWordAroundCaret();
    }

    /**
     * @see View#onWindowFocusChanged(boolean)
     */
    public void onWindowFocusChanged(boolean hasWindowFocus) {
        if (!hasWindowFocus) resetGestureDetection();
    }

    public void onFocusChanged(boolean gainFocus) {
        if (!gainFocus) {
            hideImeIfNeeded();
            cancelRequestToScrollFocusedEditableNodeIntoView();
            hidePastePopup();
            hideTextHandles();
        }
        if (mNativeContentViewCore != 0) nativeSetFocus(mNativeContentViewCore, gainFocus);
    }

    /**
     * @see View#onKeyUp(int, KeyEvent)
     */
    public boolean onKeyUp(int keyCode, KeyEvent event) {
        if (mPopupZoomer.isShowing() && keyCode == KeyEvent.KEYCODE_BACK) {
            mPopupZoomer.hide(true);
            return true;
        }
        return mContainerViewInternals.super_onKeyUp(keyCode, event);
    }

    /**
     * @see View#dispatchKeyEventPreIme(KeyEvent)
     */
    public boolean dispatchKeyEventPreIme(KeyEvent event) {
        try {
            TraceEvent.begin();
            return mContainerViewInternals.super_dispatchKeyEventPreIme(event);
        } finally {
            TraceEvent.end();
        }
    }

    /**
     * @see View#dispatchKeyEvent(KeyEvent)
     */
    public boolean dispatchKeyEvent(KeyEvent event) {
        if (GamepadList.dispatchKeyEvent(event)) return true;
        if (getContentViewClient().shouldOverrideKeyEvent(event)) {
            return mContainerViewInternals.super_dispatchKeyEvent(event);
        }

        if (mImeAdapter.dispatchKeyEvent(event)) return true;

        return mContainerViewInternals.super_dispatchKeyEvent(event);
    }

    /**
     * @see View#onHoverEvent(MotionEvent)
     * Mouse move events are sent on hover enter, hover move and hover exit.
     * They are sent on hover exit because sometimes it acts as both a hover
     * move and hover exit.
     */
    public boolean onHoverEvent(MotionEvent event) {
        TraceEvent.begin("onHoverEvent");
        MotionEvent offset = createOffsetMotionEvent(event);
        try {
            if (mBrowserAccessibilityManager != null) {
                return mBrowserAccessibilityManager.onHoverEvent(offset);
            }

            // Work around Android bug where the x, y coordinates of a hover exit
            // event are incorrect when touch exploration is on.
            if (mTouchExplorationEnabled && offset.getAction() == MotionEvent.ACTION_HOVER_EXIT) {
                return true;
            }

            mContainerView.removeCallbacks(mFakeMouseMoveRunnable);
            if (mNativeContentViewCore != 0) {
                nativeSendMouseMoveEvent(mNativeContentViewCore, offset.getEventTime(),
                        offset.getX(), offset.getY());
            }
            return true;
        } finally {
            offset.recycle();
            TraceEvent.end("onHoverEvent");
        }
    }

    /**
     * @see View#onGenericMotionEvent(MotionEvent)
     */
    public boolean onGenericMotionEvent(MotionEvent event) {
        if (GamepadList.onGenericMotionEvent(event)) return true;
        if ((event.getSource() & InputDevice.SOURCE_CLASS_POINTER) != 0) {
            switch (event.getAction()) {
                case MotionEvent.ACTION_SCROLL:
                    if (mNativeContentViewCore == 0) return false;

                    nativeSendMouseWheelEvent(mNativeContentViewCore, event.getEventTime(),
                            event.getX(), event.getY(),
                            event.getAxisValue(MotionEvent.AXIS_VSCROLL));

                    mContainerView.removeCallbacks(mFakeMouseMoveRunnable);
                    // Send a delayed onMouseMove event so that we end
                    // up hovering over the right position after the scroll.
                    final MotionEvent eventFakeMouseMove = MotionEvent.obtain(event);
                    mFakeMouseMoveRunnable = new Runnable() {
                        @Override
                        public void run() {
                            onHoverEvent(eventFakeMouseMove);
                            eventFakeMouseMove.recycle();
                        }
                    };
                    mContainerView.postDelayed(mFakeMouseMoveRunnable, 250);
                    return true;
            }
        }
        return mContainerViewInternals.super_onGenericMotionEvent(event);
    }

    /**
     * Sets the current amount to offset incoming touch events by.  This is used to handle content
     * moving and not lining up properly with the android input system.
     * @param dx The X offset in pixels to shift touch events.
     * @param dy The Y offset in pixels to shift touch events.
     */
    public void setCurrentMotionEventOffsets(float dx, float dy) {
        mCurrentTouchOffsetX = dx;
        mCurrentTouchOffsetY = dy;
    }

    private MotionEvent createOffsetMotionEvent(MotionEvent src) {
        MotionEvent dst = MotionEvent.obtain(src);
        dst.offsetLocation(mCurrentTouchOffsetX, mCurrentTouchOffsetY);
        return dst;
    }

    /**
     * @see View#scrollBy(int, int)
     * Currently the ContentView scrolling happens in the native side. In
     * the Java view system, it is always pinned at (0, 0). scrollBy() and scrollTo()
     * are overridden, so that View's mScrollX and mScrollY will be unchanged at
     * (0, 0). This is critical for drawing ContentView correctly.
     */
    public void scrollBy(int xPix, int yPix) {
        if (mNativeContentViewCore != 0) {
            nativeScrollBy(mNativeContentViewCore,
                    SystemClock.uptimeMillis(), 0, 0, xPix, yPix);
        }
    }

    /**
     * @see View#scrollTo(int, int)
     */
    public void scrollTo(int xPix, int yPix) {
        if (mNativeContentViewCore == 0) return;
        final float xCurrentPix = mRenderCoordinates.getScrollXPix();
        final float yCurrentPix = mRenderCoordinates.getScrollYPix();
        final float dxPix = xPix - xCurrentPix;
        final float dyPix = yPix - yCurrentPix;
        if (dxPix != 0 || dyPix != 0) {
            long time = SystemClock.uptimeMillis();
            nativeScrollBegin(mNativeContentViewCore, time,
                    xCurrentPix, yCurrentPix, -dxPix, -dyPix);
            nativeScrollBy(mNativeContentViewCore,
                    time, xCurrentPix, yCurrentPix, dxPix, dyPix);
            nativeScrollEnd(mNativeContentViewCore, time);
        }
    }

    // NOTE: this can go away once ContentView.getScrollX() reports correct values.
    //       see: b/6029133
    public int getNativeScrollXForTest() {
        return mRenderCoordinates.getScrollXPixInt();
    }

    // NOTE: this can go away once ContentView.getScrollY() reports correct values.
    //       see: b/6029133
    public int getNativeScrollYForTest() {
        return mRenderCoordinates.getScrollYPixInt();
    }

    /**
     * @see View#computeHorizontalScrollExtent()
     */
    @SuppressWarnings("javadoc")
    public int computeHorizontalScrollExtent() {
        return mRenderCoordinates.getLastFrameViewportWidthPixInt();
    }

    /**
     * @see View#computeHorizontalScrollOffset()
     */
    @SuppressWarnings("javadoc")
    public int computeHorizontalScrollOffset() {
        return mRenderCoordinates.getScrollXPixInt();
    }

    /**
     * @see View#computeHorizontalScrollRange()
     */
    @SuppressWarnings("javadoc")
    public int computeHorizontalScrollRange() {
        return mRenderCoordinates.getContentWidthPixInt();
    }

    /**
     * @see View#computeVerticalScrollExtent()
     */
    @SuppressWarnings("javadoc")
    public int computeVerticalScrollExtent() {
        return mRenderCoordinates.getLastFrameViewportHeightPixInt();
    }

    /**
     * @see View#computeVerticalScrollOffset()
     */
    @SuppressWarnings("javadoc")
    public int computeVerticalScrollOffset() {
        return mRenderCoordinates.getScrollYPixInt();
    }

    /**
     * @see View#computeVerticalScrollRange()
     */
    @SuppressWarnings("javadoc")
    public int computeVerticalScrollRange() {
        return mRenderCoordinates.getContentHeightPixInt();
    }

    // End FrameLayout overrides.

    /**
     * @see View#awakenScrollBars(int, boolean)
     */
    @SuppressWarnings("javadoc")
    public boolean awakenScrollBars(int startDelay, boolean invalidate) {
        // For the default implementation of ContentView which draws the scrollBars on the native
        // side, calling this function may get us into a bad state where we keep drawing the
        // scrollBars, so disable it by always returning false.
        if (mContainerView.getScrollBarStyle() == View.SCROLLBARS_INSIDE_OVERLAY) {
            return false;
        } else {
            return mContainerViewInternals.super_awakenScrollBars(startDelay, invalidate);
        }
    }

    private void updateForTapOrPress(int type, float xPix, float yPix) {
        if (type != GestureEventType.SINGLE_TAP_CONFIRMED
                && type != GestureEventType.SINGLE_TAP_UP
                && type != GestureEventType.LONG_PRESS
                && type != GestureEventType.LONG_TAP) {
            return;
        }

        if (mContainerView.isFocusable() && mContainerView.isFocusableInTouchMode()
                && !mContainerView.isFocused())  {
            mContainerView.requestFocus();
        }

        if (!mPopupZoomer.isShowing()) mPopupZoomer.setLastTouch(xPix, yPix);

        mLastTapX = (int) xPix;
        mLastTapY = (int) yPix;
    }

    /**
     * @return The x coordinate for the last point that a tap or press gesture was initiated from.
     */
    public int getLastTapX()  {
        return mLastTapX;
    }

    /**
     * @return The y coordinate for the last point that a tap or press gesture was initiated from.
     */
    public int getLastTapY()  {
        return mLastTapY;
    }

    public void setZoomControlsDelegate(ZoomControlsDelegate zoomControlsDelegate) {
        mZoomControlsDelegate = zoomControlsDelegate;
    }

    public void updateMultiTouchZoomSupport(boolean supportsMultiTouchZoom) {
        if (mNativeContentViewCore == 0) return;
        nativeSetMultiTouchZoomSupportEnabled(mNativeContentViewCore, supportsMultiTouchZoom);
    }

    public void updateDoubleTapSupport(boolean supportsDoubleTap) {
        if (mNativeContentViewCore == 0) return;
        nativeSetDoubleTapSupportEnabled(mNativeContentViewCore, supportsDoubleTap);
    }

    public void selectPopupMenuItems(int[] indices) {
        if (mNativeContentViewCore != 0) {
            nativeSelectPopupMenuItems(mNativeContentViewCore, indices);
        }
        mSelectPopup = null;
    }

    /**
     * Send the screen orientation value to the renderer.
     */
    @VisibleForTesting
    void sendOrientationChangeEvent(int orientation) {
        if (mNativeContentViewCore == 0) return;

        nativeSendOrientationChangeEvent(mNativeContentViewCore, orientation);
    }

    /**
     * Register the delegate to be used when content can not be handled by
     * the rendering engine, and should be downloaded instead. This will replace
     * the current delegate, if any.
     * @param delegate An implementation of ContentViewDownloadDelegate.
     */
    public void setDownloadDelegate(ContentViewDownloadDelegate delegate) {
        mDownloadDelegate = delegate;
    }

    // Called by DownloadController.
    ContentViewDownloadDelegate getDownloadDelegate() {
        return mDownloadDelegate;
    }

    private void showSelectActionBar() {
        if (mActionMode != null) {
            mActionMode.invalidate();
            return;
        }

        // Start a new action mode with a SelectActionModeCallback.
        SelectActionModeCallback.ActionHandler actionHandler =
                new SelectActionModeCallback.ActionHandler() {
            @Override
            public void selectAll() {
                mImeAdapter.selectAll();
            }

            @Override
            public void cut() {
                mImeAdapter.cut();
            }

            @Override
            public void copy() {
                mImeAdapter.copy();
            }

            @Override
            public void paste() {
                mImeAdapter.paste();
            }

            @Override
            public void share() {
                final String query = getSelectedText();
                if (TextUtils.isEmpty(query)) return;

                Intent send = new Intent(Intent.ACTION_SEND);
                send.setType("text/plain");
                send.putExtra(Intent.EXTRA_TEXT, query);
                try {
                    Intent i = Intent.createChooser(send, getContext().getString(
                            R.string.actionbar_share));
                    i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                    getContext().startActivity(i);
                } catch (android.content.ActivityNotFoundException ex) {
                    // If no app handles it, do nothing.
                }
            }

            @Override
            public void search() {
                final String query = getSelectedText();
                if (TextUtils.isEmpty(query)) return;

                // See if ContentViewClient wants to override
                if (getContentViewClient().doesPerformWebSearch()) {
                    getContentViewClient().performWebSearch(query);
                    return;
                }

                Intent i = new Intent(Intent.ACTION_WEB_SEARCH);
                i.putExtra(SearchManager.EXTRA_NEW_SEARCH, true);
                i.putExtra(SearchManager.QUERY, query);
                i.putExtra(Browser.EXTRA_APPLICATION_ID, getContext().getPackageName());
                if (!(getContext() instanceof Activity)) {
                    i.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                }
                try {
                    getContext().startActivity(i);
                } catch (android.content.ActivityNotFoundException ex) {
                    // If no app handles it, do nothing.
                }
            }

            @Override
            public boolean isSelectionPassword() {
                return mImeAdapter.isSelectionPassword();
            }

            @Override
            public boolean isSelectionEditable() {
                return mFocusedNodeEditable;
            }

            @Override
            public void onDestroyActionMode() {
                mActionMode = null;
                if (mUnselectAllOnActionModeDismiss) {
                    hideTextHandles();
                    if (isSelectionEditable()) {
                        int selectionEnd = Selection.getSelectionEnd(mEditable);
                        mInputConnection.setSelection(selectionEnd, selectionEnd);
                    } else {
                        mImeAdapter.unselect();
                    }
                }
                getContentViewClient().onContextualActionBarHidden();
            }

            @Override
            public boolean isShareAvailable() {
                Intent intent = new Intent(Intent.ACTION_SEND);
                intent.setType("text/plain");
                return getContext().getPackageManager().queryIntentActivities(intent,
                        PackageManager.MATCH_DEFAULT_ONLY).size() > 0;
            }

            @Override
            public boolean isWebSearchAvailable() {
                if (getContentViewClient().doesPerformWebSearch()) return true;
                Intent intent = new Intent(Intent.ACTION_WEB_SEARCH);
                intent.putExtra(SearchManager.EXTRA_NEW_SEARCH, true);
                return getContext().getPackageManager().queryIntentActivities(intent,
                        PackageManager.MATCH_DEFAULT_ONLY).size() > 0;
            }
        };
        mActionMode = null;
        // On ICS, startActionMode throws an NPE when getParent() is null.
        if (mContainerView.getParent() != null) {
            mActionMode = mContainerView.startActionMode(
                    getContentViewClient().getSelectActionModeCallback(getContext(), actionHandler,
                            nativeIsIncognito(mNativeContentViewCore)));
        }
        mUnselectAllOnActionModeDismiss = true;
        if (mActionMode == null) {
            // There is no ActionMode, so remove the selection.
            mImeAdapter.unselect();
        } else {
            getContentViewClient().onContextualActionBarShown();
        }
    }

    private void hidePastePopup() {
        if (mPastePopupMenu == null) return;
        mPastePopupMenu.hide();
    }

    @CalledByNative
    private void onSelectionEvent(int eventType, float posXDip, float posYDip) {
        switch (eventType) {
            case SelectionEventType.SELECTION_SHOWN:
                mHasSelection = true;
                // TODO(cjhopman): Remove this when there is a better signal that long press caused
                // a selection. See http://crbug.com/150151.
                mContainerView.performHapticFeedback(HapticFeedbackConstants.LONG_PRESS);
                showSelectActionBar();
                break;

            case SelectionEventType.SELECTION_CLEARED:
                mHasSelection = false;
                mUnselectAllOnActionModeDismiss = false;
                hideSelectActionBar();
                break;

            case SelectionEventType.INSERTION_SHOWN:
                mHasInsertion = true;
                break;

            case SelectionEventType.INSERTION_MOVED:
                // TODO(jdduke): Handle case where movement triggered by focus.
                hidePastePopup();
                break;

            case SelectionEventType.INSERTION_TAPPED:
                if (getPastePopup().isShowing())
                    mPastePopupMenu.hide();
                else
                    showPastePopup((int) posXDip, (int) posYDip);
                break;

            case SelectionEventType.INSERTION_CLEARED:
                mHasInsertion = false;
                hidePastePopup();
                break;

            default:
                assert false : "Invalid selection event type.";
        }
    }

    public boolean getUseDesktopUserAgent() {
        if (mNativeContentViewCore != 0) {
            return nativeGetUseDesktopUserAgent(mNativeContentViewCore);
        }
        return false;
    }

    /**
     * Set whether or not we're using a desktop user agent for the currently loaded page.
     * @param override If true, use a desktop user agent.  Use a mobile one otherwise.
     * @param reloadOnChange Reload the page if the UA has changed.
     */
    public void setUseDesktopUserAgent(boolean override, boolean reloadOnChange) {
        if (mNativeContentViewCore != 0) {
            nativeSetUseDesktopUserAgent(mNativeContentViewCore, override, reloadOnChange);
        }
    }

    public void clearSslPreferences() {
        if (mNativeContentViewCore != 0) nativeClearSslPreferences(mNativeContentViewCore);
    }

    private void hideTextHandles() {
        mHasSelection = false;
        mHasInsertion = false;
        if (mNativeContentViewCore != 0) nativeHideTextHandles(mNativeContentViewCore);
    }

    /**
     * Shows the IME if the focused widget could accept text input.
     */
    public void showImeIfNeeded() {
        assert mWebContents != null;
        mWebContents.showImeIfNeeded();
    }

    /**
     * Hides the IME if the containerView is the active view for IME.
     */
    public void hideImeIfNeeded() {
        // Hide input method window from the current view synchronously
        // because ImeAdapter does so asynchronouly with a delay, and
        // by the time when ImeAdapter dismisses the input, the
        // containerView may have lost focus.
        // We cannot trust ContentViewClient#onImeStateChangeRequested to
        // hide the input window because it has an empty default implementation.
        // So we need to explicitly hide the input method window here.
        if (mInputMethodManagerWrapper.isActive(mContainerView)) {
            mInputMethodManagerWrapper.hideSoftInputFromWindow(
                    mContainerView.getWindowToken(), 0, null);
        }
        getContentViewClient().onImeStateChangeRequested(false);
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void updateFrameInfo(
            float scrollOffsetX, float scrollOffsetY,
            float pageScaleFactor, float minPageScaleFactor, float maxPageScaleFactor,
            float contentWidth, float contentHeight,
            float viewportWidth, float viewportHeight,
            float controlsOffsetYCss, float contentOffsetYCss,
            float overdrawBottomHeightCss) {
        TraceEvent.begin("ContentViewCore:updateFrameInfo");
        // Adjust contentWidth/Height to be always at least as big as
        // the actual viewport (as set by onSizeChanged).
        final float deviceScale = mRenderCoordinates.getDeviceScaleFactor();
        contentWidth = Math.max(contentWidth,
                mViewportWidthPix / (deviceScale * pageScaleFactor));
        contentHeight = Math.max(contentHeight,
                mViewportHeightPix / (deviceScale * pageScaleFactor));
        final float contentOffsetYPix = mRenderCoordinates.fromDipToPix(contentOffsetYCss);

        final boolean contentSizeChanged =
                contentWidth != mRenderCoordinates.getContentWidthCss()
                || contentHeight != mRenderCoordinates.getContentHeightCss();
        final boolean scaleLimitsChanged =
                minPageScaleFactor != mRenderCoordinates.getMinPageScaleFactor()
                || maxPageScaleFactor != mRenderCoordinates.getMaxPageScaleFactor();
        final boolean pageScaleChanged =
                pageScaleFactor != mRenderCoordinates.getPageScaleFactor();
        final boolean scrollChanged =
                pageScaleChanged
                || scrollOffsetX != mRenderCoordinates.getScrollX()
                || scrollOffsetY != mRenderCoordinates.getScrollY();
        final boolean contentOffsetChanged =
                contentOffsetYPix != mRenderCoordinates.getContentOffsetYPix();

        final boolean needHidePopupZoomer = contentSizeChanged || scrollChanged;
        final boolean needUpdateZoomControls = scaleLimitsChanged || scrollChanged;

        if (needHidePopupZoomer) mPopupZoomer.hide(true);

        if (scrollChanged) {
            mContainerViewInternals.onScrollChanged(
                    (int) mRenderCoordinates.fromLocalCssToPix(scrollOffsetX),
                    (int) mRenderCoordinates.fromLocalCssToPix(scrollOffsetY),
                    (int) mRenderCoordinates.getScrollXPix(),
                    (int) mRenderCoordinates.getScrollYPix());
        }

        mRenderCoordinates.updateFrameInfo(
                scrollOffsetX, scrollOffsetY,
                contentWidth, contentHeight,
                viewportWidth, viewportHeight,
                pageScaleFactor, minPageScaleFactor, maxPageScaleFactor,
                contentOffsetYPix);

        if (scrollChanged || contentOffsetChanged) {
            for (mGestureStateListenersIterator.rewind();
                    mGestureStateListenersIterator.hasNext();) {
                mGestureStateListenersIterator.next().onScrollOffsetOrExtentChanged(
                        computeVerticalScrollOffset(),
                        computeVerticalScrollExtent());
            }
        }

        if (needUpdateZoomControls) mZoomControlsDelegate.updateZoomControls();

        // Update offsets for fullscreen.
        final float controlsOffsetPix = controlsOffsetYCss * deviceScale;
        final float overdrawBottomHeightPix = overdrawBottomHeightCss * deviceScale;
        getContentViewClient().onOffsetsForFullscreenChanged(
                controlsOffsetPix, contentOffsetYPix, overdrawBottomHeightPix);

        if (mBrowserAccessibilityManager != null) {
            mBrowserAccessibilityManager.notifyFrameInfoInitialized();
        }
        TraceEvent.end("ContentViewCore:updateFrameInfo");
    }

    @CalledByNative
    private void updateImeAdapter(long nativeImeAdapterAndroid, int textInputType,
            String text, int selectionStart, int selectionEnd,
            int compositionStart, int compositionEnd, boolean showImeIfNeeded,
            boolean isNonImeChange) {
        TraceEvent.begin();
        mFocusedNodeEditable = (textInputType != ImeAdapter.getTextInputTypeNone());
        if (!mFocusedNodeEditable) hidePastePopup();

        mImeAdapter.updateKeyboardVisibility(
                nativeImeAdapterAndroid, textInputType, showImeIfNeeded);

        if (mInputConnection != null) {
            mInputConnection.updateState(text, selectionStart, selectionEnd, compositionStart,
                    compositionEnd, isNonImeChange);
        }

        if (mActionMode != null) mActionMode.invalidate();
        TraceEvent.end();
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void setTitle(String title) {
        getContentViewClient().onUpdateTitle(title);
    }

    /**
     * Called (from native) when the <select> popup needs to be shown.
     * @param items           Items to show.
     * @param enabled         POPUP_ITEM_TYPEs for items.
     * @param multiple        Whether the popup menu should support multi-select.
     * @param selectedIndices Indices of selected items.
     */
    @SuppressWarnings("unused")
    @CalledByNative
    private void showSelectPopup(Rect bounds, String[] items, int[] enabled, boolean multiple,
            int[] selectedIndices) {
        if (mContainerView.getParent() == null || mContainerView.getVisibility() != View.VISIBLE) {
            selectPopupMenuItems(null);
            return;
        }

        assert items.length == enabled.length;
        List<SelectPopupItem> popupItems = new ArrayList<SelectPopupItem>();
        for (int i = 0; i < items.length; i++) {
            popupItems.add(new SelectPopupItem(items[i], enabled[i]));
        }
        hidePopups();
        if (DeviceFormFactor.isTablet(mContext) && !multiple) {
            mSelectPopup = new SelectPopupDropdown(this, popupItems, bounds, selectedIndices);
        } else {
            mSelectPopup = new SelectPopupDialog(this, popupItems, multiple, selectedIndices);
        }
        mSelectPopup.show();
    }

    /**
     * Called when the <select> popup needs to be hidden.
     */
    @CalledByNative
    private void hideSelectPopup() {
        if (mSelectPopup != null) mSelectPopup.hide();
    }

    /**
     * @return The visible select popup being shown.
     */
    public SelectPopup getSelectPopupForTest() {
        return mSelectPopup;
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void showDisambiguationPopup(Rect targetRect, Bitmap zoomedBitmap) {
        mPopupZoomer.setBitmap(zoomedBitmap);
        mPopupZoomer.show(targetRect);
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private TouchEventSynthesizer createTouchEventSynthesizer() {
        return new TouchEventSynthesizer(this);
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private PopupTouchHandleDrawable createPopupTouchHandleDrawable() {
        if (mTouchHandleDelegate == null) {
            mTouchHandleDelegate = new PopupTouchHandleDrawableDelegate() {
                public View getParent() {
                    return getContainerView();
                }

                public PositionObserver getParentPositionObserver() {
                    return mPositionObserver;
                }

                public boolean onTouchHandleEvent(MotionEvent event) {
                    final boolean isTouchHandleEvent = true;
                    return onTouchEventImpl(event, isTouchHandleEvent);
                }
            };
        }
        return new PopupTouchHandleDrawable(mTouchHandleDelegate);
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void onSelectionChanged(String text) {
        mLastSelectedText = text;
        getContentViewClient().onSelectionChanged(text);
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private static void onEvaluateJavaScriptResult(
            String jsonResult, JavaScriptCallback callback) {
        callback.handleJavaScriptResult(jsonResult);
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void showPastePopup(int xDip, int yDip) {
        if (!mHasInsertion) return;
        final float contentOffsetYPix = mRenderCoordinates.getContentOffsetYPix();
        getPastePopup().showAt(
            (int) mRenderCoordinates.fromDipToPix(xDip),
            (int) (mRenderCoordinates.fromDipToPix(yDip) + contentOffsetYPix));
    }

    private PastePopupMenu getPastePopup() {
        if (mPastePopupMenu == null) {
            mPastePopupMenu = new PastePopupMenu(getContainerView(),
                new PastePopupMenuDelegate() {
                    public void paste() {
                        mImeAdapter.paste();
                        hideTextHandles();
                    }
                    public boolean canPaste() {
                        if (!mFocusedNodeEditable) return false;
                        return ((ClipboardManager) mContext.getSystemService(
                                Context.CLIPBOARD_SERVICE)).hasPrimaryClip();
                    }
                });
        }
        return mPastePopupMenu;
    }

    @SuppressWarnings("unused")
    @CalledByNative
    private void onRenderProcessChange() {
        attachImeAdapter();
    }

    /**
     * Attaches the native ImeAdapter object to the java ImeAdapter to allow communication via JNI.
     */
    public void attachImeAdapter() {
        if (mImeAdapter != null && mNativeContentViewCore != 0) {
            mImeAdapter.attach(nativeGetNativeImeAdapter(mNativeContentViewCore));
        }
    }

    /**
     * @see View#hasFocus()
     */
    @CalledByNative
    public boolean hasFocus() {
        return mContainerView.hasFocus();
    }

    /**
     * Checks whether the ContentViewCore can be zoomed in.
     *
     * @return True if the ContentViewCore can be zoomed in.
     */
    // This method uses the term 'zoom' for legacy reasons, but relates
    // to what chrome calls the 'page scale factor'.
    public boolean canZoomIn() {
        final float zoomInExtent = mRenderCoordinates.getMaxPageScaleFactor()
                - mRenderCoordinates.getPageScaleFactor();
        return zoomInExtent > ZOOM_CONTROLS_EPSILON;
    }

    /**
     * Checks whether the ContentViewCore can be zoomed out.
     *
     * @return True if the ContentViewCore can be zoomed out.
     */
    // This method uses the term 'zoom' for legacy reasons, but relates
    // to what chrome calls the 'page scale factor'.
    public boolean canZoomOut() {
        final float zoomOutExtent = mRenderCoordinates.getPageScaleFactor()
                - mRenderCoordinates.getMinPageScaleFactor();
        return zoomOutExtent > ZOOM_CONTROLS_EPSILON;
    }

    /**
     * Zooms in the ContentViewCore by 25% (or less if that would result in
     * zooming in more than possible).
     *
     * @return True if there was a zoom change, false otherwise.
     */
    // This method uses the term 'zoom' for legacy reasons, but relates
    // to what chrome calls the 'page scale factor'.
    public boolean zoomIn() {
        if (!canZoomIn()) {
            return false;
        }
        return pinchByDelta(1.25f);
    }

    /**
     * Zooms out the ContentViewCore by 20% (or less if that would result in
     * zooming out more than possible).
     *
     * @return True if there was a zoom change, false otherwise.
     */
    // This method uses the term 'zoom' for legacy reasons, but relates
    // to what chrome calls the 'page scale factor'.
    public boolean zoomOut() {
        if (!canZoomOut()) {
            return false;
        }
        return pinchByDelta(0.8f);
    }

    /**
     * Resets the zoom factor of the ContentViewCore.
     *
     * @return True if there was a zoom change, false otherwise.
     */
    // This method uses the term 'zoom' for legacy reasons, but relates
    // to what chrome calls the 'page scale factor'.
    public boolean zoomReset() {
        // The page scale factor is initialized to mNativeMinimumScale when
        // the page finishes loading. Thus sets it back to mNativeMinimumScale.
        if (!canZoomOut()) return false;
        return pinchByDelta(
                mRenderCoordinates.getMinPageScaleFactor()
                        / mRenderCoordinates.getPageScaleFactor());
    }

    /**
     * Simulate a pinch zoom gesture.
     *
     * @param delta the factor by which the current page scale should be multiplied by.
     * @return whether the gesture was sent.
     */
    public boolean pinchByDelta(float delta) {
        if (mNativeContentViewCore == 0) return false;

        long timeMs = SystemClock.uptimeMillis();
        int xPix = getViewportWidthPix() / 2;
        int yPix = getViewportHeightPix() / 2;

        nativePinchBegin(mNativeContentViewCore, timeMs, xPix, yPix);
        nativePinchBy(mNativeContentViewCore, timeMs, xPix, yPix, delta);
        nativePinchEnd(mNativeContentViewCore, timeMs);

        return true;
    }

    /**
     * Invokes the graphical zoom picker widget for this ContentView.
     */
    public void invokeZoomPicker() {
        mZoomControlsDelegate.invokeZoomPicker();
    }

    /**
     * Enables or disables inspection of JavaScript objects added via
     * {@link #addJavascriptInterface(Object, String)} by means of Object.keys() method and
     * &quot;for .. in&quot; loop. Being able to inspect JavaScript objects is useful
     * when debugging hybrid Android apps, but can't be enabled for legacy applications due
     * to compatibility risks.
     *
     * @param allow Whether to allow JavaScript objects inspection.
     */
    public void setAllowJavascriptInterfacesInspection(boolean allow) {
        nativeSetAllowJavascriptInterfacesInspection(mNativeContentViewCore, allow);
    }

    /**
     * Returns JavaScript interface objects previously injected via
     * {@link #addJavascriptInterface(Object, String)}.
     *
     * @return the mapping of names to interface objects and corresponding annotation classes
     */
    public Map<String, Pair<Object, Class>> getJavascriptInterfaces() {
        return mJavaScriptInterfaces;
    }

    /**
     * This will mimic {@link #addPossiblyUnsafeJavascriptInterface(Object, String, Class)}
     * and automatically pass in {@link JavascriptInterface} as the required annotation.
     *
     * @param object The Java object to inject into the ContentViewCore's JavaScript context.  Null
     *               values are ignored.
     * @param name   The name used to expose the instance in JavaScript.
     */
    public void addJavascriptInterface(Object object, String name) {
        addPossiblyUnsafeJavascriptInterface(object, name, JavascriptInterface.class);
    }

    /**
     * This method injects the supplied Java object into the ContentViewCore.
     * The object is injected into the JavaScript context of the main frame,
     * using the supplied name. This allows the Java object to be accessed from
     * JavaScript. Note that that injected objects will not appear in
     * JavaScript until the page is next (re)loaded. For example:
     * <pre> view.addJavascriptInterface(new Object(), "injectedObject");
     * view.loadData("<!DOCTYPE html><title></title>", "text/html", null);
     * view.loadUrl("javascript:alert(injectedObject.toString())");</pre>
     * <p><strong>IMPORTANT:</strong>
     * <ul>
     * <li> addJavascriptInterface() can be used to allow JavaScript to control
     * the host application. This is a powerful feature, but also presents a
     * security risk. Use of this method in a ContentViewCore containing
     * untrusted content could allow an attacker to manipulate the host
     * application in unintended ways, executing Java code with the permissions
     * of the host application. Use extreme care when using this method in a
     * ContentViewCore which could contain untrusted content. Particular care
     * should be taken to avoid unintentional access to inherited methods, such
     * as {@link Object#getClass()}. To prevent access to inherited methods,
     * pass an annotation for {@code requiredAnnotation}.  This will ensure
     * that only methods with {@code requiredAnnotation} are exposed to the
     * Javascript layer.  {@code requiredAnnotation} will be passed to all
     * subsequently injected Java objects if any methods return an object.  This
     * means the same restrictions (or lack thereof) will apply.  Alternatively,
     * {@link #addJavascriptInterface(Object, String)} can be called, which
     * automatically uses the {@link JavascriptInterface} annotation.
     * <li> JavaScript interacts with Java objects on a private, background
     * thread of the ContentViewCore. Care is therefore required to maintain
     * thread safety.</li>
     * </ul></p>
     *
     * @param object             The Java object to inject into the
     *                           ContentViewCore's JavaScript context. Null
     *                           values are ignored.
     * @param name               The name used to expose the instance in
     *                           JavaScript.
     * @param requiredAnnotation Restrict exposed methods to ones with this
     *                           annotation.  If {@code null} all methods are
     *                           exposed.
     *
     */
    public void addPossiblyUnsafeJavascriptInterface(Object object, String name,
            Class<? extends Annotation> requiredAnnotation) {
        if (mNativeContentViewCore != 0 && object != null) {
            mJavaScriptInterfaces.put(name, new Pair<Object, Class>(object, requiredAnnotation));
            nativeAddJavascriptInterface(mNativeContentViewCore, object, name, requiredAnnotation);
        }
    }

    /**
     * Removes a previously added JavaScript interface with the given name.
     *
     * @param name The name of the interface to remove.
     */
    public void removeJavascriptInterface(String name) {
        mJavaScriptInterfaces.remove(name);
        if (mNativeContentViewCore != 0) {
            nativeRemoveJavascriptInterface(mNativeContentViewCore, name);
        }
    }

    /**
     * Return the current scale of the ContentView.
     * @return The current page scale factor.
     */
    public float getScale() {
        return mRenderCoordinates.getPageScaleFactor();
    }

    /**
     * If the view is ready to draw contents to the screen. In hardware mode,
     * the initialization of the surface texture may not occur until after the
     * view has been added to the layout. This method will return {@code true}
     * once the texture is actually ready.
     */
    public boolean isReady() {
        assert mWebContents != null;
        return mWebContents.isReady();
    }

    @CalledByNative
    private void startContentIntent(String contentUrl) {
        getContentViewClient().onStartContentIntent(getContext(), contentUrl);
    }

    @Override
    public void onAccessibilityStateChanged(boolean enabled) {
        setAccessibilityState(enabled);
    }

    /**
     * Determines whether or not this ContentViewCore can handle this accessibility action.
     * @param action The action to perform.
     * @return Whether or not this action is supported.
     */
    public boolean supportsAccessibilityAction(int action) {
        return mAccessibilityInjector.supportsAccessibilityAction(action);
    }

    /**
     * Attempts to perform an accessibility action on the web content.  If the accessibility action
     * cannot be processed, it returns {@code null}, allowing the caller to know to call the
     * super {@link View#performAccessibilityAction(int, Bundle)} method and use that return value.
     * Otherwise the return value from this method should be used.
     * @param action The action to perform.
     * @param arguments Optional action arguments.
     * @return Whether the action was performed or {@code null} if the call should be delegated to
     *         the super {@link View} class.
     */
    public boolean performAccessibilityAction(int action, Bundle arguments) {
        if (mAccessibilityInjector.supportsAccessibilityAction(action)) {
            return mAccessibilityInjector.performAccessibilityAction(action, arguments);
        }

        return false;
    }

    /**
     * Set the BrowserAccessibilityManager, used for native accessibility
     * (not script injection). This is only set when system accessibility
     * has been enabled.
     * @param manager The new BrowserAccessibilityManager.
     */
    public void setBrowserAccessibilityManager(BrowserAccessibilityManager manager) {
        mBrowserAccessibilityManager = manager;
    }

    /**
     * Get the BrowserAccessibilityManager, used for native accessibility
     * (not script injection). This will return null when system accessibility
     * is not enabled.
     * @return This view's BrowserAccessibilityManager.
     */
    public BrowserAccessibilityManager getBrowserAccessibilityManager() {
        return mBrowserAccessibilityManager;
    }

    /**
     * If native accessibility (not script injection) is enabled, and if this is
     * running on JellyBean or later, returns an AccessibilityNodeProvider that
     * implements native accessibility for this view. Returns null otherwise.
     * Lazily initializes native accessibility here if it's allowed.
     * @return The AccessibilityNodeProvider, if available, or null otherwise.
     */
    public AccessibilityNodeProvider getAccessibilityNodeProvider() {
        if (mBrowserAccessibilityManager != null) {
            return mBrowserAccessibilityManager.getAccessibilityNodeProvider();
        }

        if (mNativeAccessibilityAllowed &&
                !mNativeAccessibilityEnabled &&
                mNativeContentViewCore != 0 &&
                Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
            mNativeAccessibilityEnabled = true;
            nativeSetAccessibilityEnabled(mNativeContentViewCore, true);
        }

        return null;
    }

    /**
     * @see View#onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo)
     */
    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
        // Note: this is only used by the script-injecting accessibility code.
        mAccessibilityInjector.onInitializeAccessibilityNodeInfo(info);
    }

    /**
     * @see View#onInitializeAccessibilityEvent(AccessibilityEvent)
     */
    public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
        // Note: this is only used by the script-injecting accessibility code.
        event.setClassName(this.getClass().getName());

        // Identify where the top-left of the screen currently points to.
        event.setScrollX(mRenderCoordinates.getScrollXPixInt());
        event.setScrollY(mRenderCoordinates.getScrollYPixInt());

        // The maximum scroll values are determined by taking the content dimensions and
        // subtracting off the actual dimensions of the ChromeView.
        int maxScrollXPix = Math.max(0, mRenderCoordinates.getMaxHorizontalScrollPixInt());
        int maxScrollYPix = Math.max(0, mRenderCoordinates.getMaxVerticalScrollPixInt());
        event.setScrollable(maxScrollXPix > 0 || maxScrollYPix > 0);

        // Setting the maximum scroll values requires API level 15 or higher.
        final int SDK_VERSION_REQUIRED_TO_SET_SCROLL = 15;
        if (Build.VERSION.SDK_INT >= SDK_VERSION_REQUIRED_TO_SET_SCROLL) {
            event.setMaxScrollX(maxScrollXPix);
            event.setMaxScrollY(maxScrollYPix);
        }
    }

    /**
     * Returns whether accessibility script injection is enabled on the device
     */
    public boolean isDeviceAccessibilityScriptInjectionEnabled() {
        try {
            // On JellyBean and higher, native accessibility is the default so script
            // injection is only allowed if enabled via a flag.
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN &&
                    !CommandLine.getInstance().hasSwitch(
                            ContentSwitches.ENABLE_ACCESSIBILITY_SCRIPT_INJECTION)) {
                return false;
            }

            if (!mContentSettings.getJavaScriptEnabled()) {
                return false;
            }

            int result = getContext().checkCallingOrSelfPermission(
                    android.Manifest.permission.INTERNET);
            if (result != PackageManager.PERMISSION_GRANTED) {
                return false;
            }

            Field field = Settings.Secure.class.getField("ACCESSIBILITY_SCRIPT_INJECTION");
            field.setAccessible(true);
            String accessibilityScriptInjection = (String) field.get(null);
            ContentResolver contentResolver = getContext().getContentResolver();

            if (mAccessibilityScriptInjectionObserver == null) {
                ContentObserver contentObserver = new ContentObserver(new Handler()) {
                    @Override
                    public void onChange(boolean selfChange, Uri uri) {
                        setAccessibilityState(mAccessibilityManager.isEnabled());
                    }
                };
                contentResolver.registerContentObserver(
                    Settings.Secure.getUriFor(accessibilityScriptInjection),
                    false,
                    contentObserver);
                mAccessibilityScriptInjectionObserver = contentObserver;
            }

            return Settings.Secure.getInt(contentResolver, accessibilityScriptInjection, 0) == 1;
        } catch (NoSuchFieldException e) {
            // Do nothing, default to false.
        } catch (IllegalAccessException e) {
            // Do nothing, default to false.
        }
        return false;
    }

    /**
     * Returns whether or not accessibility injection is being used.
     */
    public boolean isInjectingAccessibilityScript() {
        return mAccessibilityInjector.accessibilityIsAvailable();
    }

    /**
     * Returns true if accessibility is on and touch exploration is enabled.
     */
    public boolean isTouchExplorationEnabled() {
        return mTouchExplorationEnabled;
    }

    /**
     * Turns browser accessibility on or off.
     * If |state| is |false|, this turns off both native and injected accessibility.
     * Otherwise, if accessibility script injection is enabled, this will enable the injected
     * accessibility scripts. Native accessibility is enabled on demand.
     */
    public void setAccessibilityState(boolean state) {
        if (!state) {
            setInjectedAccessibility(false);
            mNativeAccessibilityAllowed = false;
            mTouchExplorationEnabled = false;
        } else {
            boolean useScriptInjection = isDeviceAccessibilityScriptInjectionEnabled();
            setInjectedAccessibility(useScriptInjection);
            mNativeAccessibilityAllowed = !useScriptInjection;
            mTouchExplorationEnabled = mAccessibilityManager.isTouchExplorationEnabled();
        }
    }

    /**
     * Enable or disable injected accessibility features
     */
    public void setInjectedAccessibility(boolean enabled) {
        mAccessibilityInjector.addOrRemoveAccessibilityApisIfNecessary();
        mAccessibilityInjector.setScriptEnabled(enabled);
    }

    /**
     * Stop any TTS notifications that are currently going on.
     */
    public void stopCurrentAccessibilityNotifications() {
        mAccessibilityInjector.onPageLostFocus();
    }

    /**
     * Inform WebKit that Fullscreen mode has been exited by the user.
     */
    public void exitFullscreen() {
        assert mWebContents != null;
        mWebContents.exitFullscreen();
    }

    /**
     * Changes whether hiding the top controls is enabled.
     *
     * @param enableHiding Whether hiding the top controls should be enabled or not.
     * @param enableShowing Whether showing the top controls should be enabled or not.
     * @param animate Whether the transition should be animated or not.
     */
    public void updateTopControlsState(boolean enableHiding, boolean enableShowing,
            boolean animate) {
        assert mWebContents != null;
        mWebContents.updateTopControlsState(
                enableHiding, enableShowing, animate);
    }

    /**
     * Callback factory method for nativeGetNavigationHistory().
     */
    @CalledByNative
    private void addToNavigationHistory(Object history, int index, String url, String virtualUrl,
            String originalUrl, String title, Bitmap favicon) {
        NavigationEntry entry = new NavigationEntry(
                index, url, virtualUrl, originalUrl, title, favicon);
        ((NavigationHistory) history).addEntry(entry);
    }

    /**
     * Get a copy of the navigation history of the view.
     */
    public NavigationHistory getNavigationHistory() {
        NavigationHistory history = new NavigationHistory();
        if (mNativeContentViewCore != 0) {
            int currentIndex = nativeGetNavigationHistory(mNativeContentViewCore, history);
            history.setCurrentEntryIndex(currentIndex);
        }
        return history;
    }

    @Override
    public NavigationHistory getDirectedNavigationHistory(boolean isForward, int itemLimit) {
        NavigationHistory history = new NavigationHistory();
        if (mNativeContentViewCore != 0) {
            nativeGetDirectedNavigationHistory(
                mNativeContentViewCore, history, isForward, itemLimit);
        }
        return history;
    }

    /**
     * @return The original request URL for the current navigation entry, or null if there is no
     *         current entry.
     */
    public String getOriginalUrlForActiveNavigationEntry() {
        if (mNativeContentViewCore != 0) {
            return nativeGetOriginalUrlForActiveNavigationEntry(mNativeContentViewCore);
        }
        return "";
    }

    /**
     * @return The cached copy of render positions and scales.
     */
    public RenderCoordinates getRenderCoordinates() {
        return mRenderCoordinates;
    }

    @CalledByNative
    private static Rect createRect(int x, int y, int right, int bottom) {
        return new Rect(x, y, right, bottom);
    }

    public void extractSmartClipData(int x, int y, int width, int height) {
        if (mNativeContentViewCore != 0) {
            x += mSmartClipOffsetX;
            y += mSmartClipOffsetY;
            nativeExtractSmartClipData(mNativeContentViewCore, x, y, width, height);
        }
    }

    /**
     * Set offsets for smart clip.
     *
     * <p>This should be called if there is a viewport change introduced by,
     * e.g., show and hide of a location bar.
     *
     * @param offsetX Offset for X position.
     * @param offsetY Offset for Y position.
     */
    public void setSmartClipOffsets(int offsetX, int offsetY) {
        mSmartClipOffsetX = offsetX;
        mSmartClipOffsetY = offsetY;
    }

    @CalledByNative
    private void onSmartClipDataExtracted(String text, String html, Rect clipRect) {
        if (mSmartClipDataListener != null ) {
            mSmartClipDataListener.onSmartClipDataExtracted(text, html, clipRect);
        }
    }

    public void setSmartClipDataListener(SmartClipDataListener listener) {
        mSmartClipDataListener = listener;
    }

    public void setBackgroundOpaque(boolean opaque) {
        if (mNativeContentViewCore != 0) {
            nativeSetBackgroundOpaque(mNativeContentViewCore, opaque);
        }
    }

    @CalledByNative
    private void didDeferAfterResponseStarted(String enteringColor) {
        if (mNavigationTransitionDelegate != null ) {
            mNavigationTransitionDelegate.didDeferAfterResponseStarted(enteringColor);
        }
    }

    @CalledByNative
    public void didStartNavigationTransitionForFrame(long frameId) {
        if (mNavigationTransitionDelegate != null ) {
            mNavigationTransitionDelegate.didStartNavigationTransitionForFrame(frameId);
        }
    }

    @CalledByNative
    private boolean willHandleDeferAfterResponseStarted() {
        if (mNavigationTransitionDelegate == null) return false;
        return mNavigationTransitionDelegate.willHandleDeferAfterResponseStarted();
    }

    @VisibleForTesting
    void setHasPendingNavigationTransitionForTesting() {
        if (mNativeContentViewCore == 0) return;
        nativeSetHasPendingNavigationTransitionForTesting(mNativeContentViewCore);
    }

    public void setNavigationTransitionDelegate(NavigationTransitionDelegate delegate) {
        mNavigationTransitionDelegate = delegate;
    }

    @CalledByNative
    private void addEnteringStylesheetToTransition(String stylesheet) {
        if (mNavigationTransitionDelegate != null ) {
            mNavigationTransitionDelegate.addEnteringStylesheetToTransition(stylesheet);
        }
    }

    /**
     * Offer a long press gesture to the embedding View, primarily for WebView compatibility.
     *
     * @return true if the embedder handled the event.
     */
    private boolean offerLongPressToEmbedder() {
        return mContainerView.performLongClick();
    }

    /**
     * Reset scroll and fling accounting, notifying listeners as appropriate.
     * This is useful as a failsafe when the input stream may have been interruped.
     */
    private void resetScrollInProgress() {
        if (!isScrollInProgress()) return;

        final boolean touchScrollInProgress = mTouchScrollInProgress;
        final int potentiallyActiveFlingCount = mPotentiallyActiveFlingCount;

        mTouchScrollInProgress = false;
        mPotentiallyActiveFlingCount = 0;

        if (touchScrollInProgress) updateGestureStateListener(GestureEventType.SCROLL_END);
        if (potentiallyActiveFlingCount > 0) updateGestureStateListener(GestureEventType.FLING_END);
    }

    private native long nativeInit(long webContentsPtr,
            long viewAndroidPtr, long windowAndroidPtr, HashSet<Object> retainedObjectSet);

    @CalledByNative
    private ContentVideoViewClient getContentVideoViewClient() {
        return getContentViewClient().getContentVideoViewClient();
    }

    @CalledByNative
    private boolean shouldBlockMediaRequest(String url) {
        return getContentViewClient().shouldBlockMediaRequest(url);
    }

    @CalledByNative
    private void onNativeFlingStopped() {
        // Note that mTouchScrollInProgress should normally be false at this
        // point, but we reset it anyway as another failsafe.
        mTouchScrollInProgress = false;
        if (mPotentiallyActiveFlingCount <= 0) return;
        mPotentiallyActiveFlingCount--;
        updateGestureStateListener(GestureEventType.FLING_END);
    }

    @Override
    public void onScreenOrientationChanged(int orientation) {
        sendOrientationChangeEvent(orientation);
    }

    public void resumeResponseDeferredAtStart() {
        if (mNativeContentViewCore == 0) return;
        nativeResumeResponseDeferredAtStart(mNativeContentViewCore);
    }

    /**
     * Set whether the ContentViewCore requires the WebContents to be fullscreen in order to lock
     * the screen orientation.
     */
    public void setFullscreenRequiredForOrientationLock(boolean value) {
        mFullscreenRequiredForOrientationLock = value;
    }

    @CalledByNative
    private boolean isFullscreenRequiredForOrientationLock() {
        return mFullscreenRequiredForOrientationLock;
    }

    private native WebContents nativeGetWebContentsAndroid(long nativeContentViewCoreImpl);

    private native void nativeOnJavaContentViewCoreDestroyed(long nativeContentViewCoreImpl);

    private native void nativeLoadUrl(
            long nativeContentViewCoreImpl,
            String url,
            int loadUrlType,
            int transitionType,
            String referrerUrl,
            int referrerPolicy,
            int uaOverrideOption,
            String extraHeaders,
            byte[] postData,
            String baseUrlForDataUrl,
            String virtualUrlForDataUrl,
            boolean canLoadLocalResources,
            boolean isRendererInitiated);

    private native String nativeGetURL(long nativeContentViewCoreImpl);

    private native boolean nativeIsIncognito(long nativeContentViewCoreImpl);

    private native void nativeSetFocus(long nativeContentViewCoreImpl, boolean focused);

    private native void nativeSendOrientationChangeEvent(
            long nativeContentViewCoreImpl, int orientation);

    // All touch events (including flings, scrolls etc) accept coordinates in physical pixels.
    private native boolean nativeOnTouchEvent(
            long nativeContentViewCoreImpl, MotionEvent event,
            long timeMs, int action, int pointerCount, int historySize, int actionIndex,
            float x0, float y0, float x1, float y1,
            int pointerId0, int pointerId1,
            float touchMajor0, float touchMajor1,
            float rawX, float rawY,
            int androidToolType0, int androidToolType1, int androidButtonState,
            boolean isTouchHandleEvent);

    private native int nativeSendMouseMoveEvent(
            long nativeContentViewCoreImpl, long timeMs, float x, float y);

    private native int nativeSendMouseWheelEvent(
            long nativeContentViewCoreImpl, long timeMs, float x, float y, float verticalAxis);

    private native void nativeScrollBegin(
            long nativeContentViewCoreImpl, long timeMs, float x, float y, float hintX,
            float hintY);

    private native void nativeScrollEnd(long nativeContentViewCoreImpl, long timeMs);

    private native void nativeScrollBy(
            long nativeContentViewCoreImpl, long timeMs, float x, float y,
            float deltaX, float deltaY);

    private native void nativeFlingStart(
            long nativeContentViewCoreImpl, long timeMs, float x, float y, float vx, float vy);

    private native void nativeFlingCancel(long nativeContentViewCoreImpl, long timeMs);

    private native void nativeSingleTap(
            long nativeContentViewCoreImpl, long timeMs, float x, float y);

    private native void nativeDoubleTap(
            long nativeContentViewCoreImpl, long timeMs, float x, float y);

    private native void nativeLongPress(
            long nativeContentViewCoreImpl, long timeMs, float x, float y);

    private native void nativePinchBegin(
            long nativeContentViewCoreImpl, long timeMs, float x, float y);

    private native void nativePinchEnd(long nativeContentViewCoreImpl, long timeMs);

    private native void nativePinchBy(long nativeContentViewCoreImpl, long timeMs,
            float anchorX, float anchorY, float deltaScale);

    private native void nativeSelectBetweenCoordinates(
            long nativeContentViewCoreImpl, float x1, float y1, float x2, float y2);

    private native void nativeMoveCaret(long nativeContentViewCoreImpl, float x, float y);

    private native void nativeHideTextHandles(long nativeContentViewCoreImpl);

    private native void nativeResetGestureDetection(long nativeContentViewCoreImpl);
    private native void nativeSetDoubleTapSupportEnabled(
            long nativeContentViewCoreImpl, boolean enabled);
    private native void nativeSetMultiTouchZoomSupportEnabled(
            long nativeContentViewCoreImpl, boolean enabled);

    private native void nativeSelectPopupMenuItems(long nativeContentViewCoreImpl, int[] indices);

    private native void nativeClearHistory(long nativeContentViewCoreImpl);

    private native void nativeEvaluateJavaScript(long nativeContentViewCoreImpl,
            String script, JavaScriptCallback callback, boolean startRenderer);

    private native void nativePostMessageToFrame(long nativeContentViewCoreImpl, String frameId,
            String message, String sourceOrigin, String targetOrigin);

    private native long nativeGetNativeImeAdapter(long nativeContentViewCoreImpl);

    private native int nativeGetCurrentRenderProcessId(long nativeContentViewCoreImpl);

    private native void nativeSetUseDesktopUserAgent(long nativeContentViewCoreImpl,
            boolean enabled, boolean reloadOnChange);
    private native boolean nativeGetUseDesktopUserAgent(long nativeContentViewCoreImpl);

    private native void nativeClearSslPreferences(long nativeContentViewCoreImpl);

    private native void nativeSetAllowJavascriptInterfacesInspection(
            long nativeContentViewCoreImpl, boolean allow);

    private native void nativeAddJavascriptInterface(long nativeContentViewCoreImpl, Object object,
            String name, Class requiredAnnotation);

    private native void nativeRemoveJavascriptInterface(long nativeContentViewCoreImpl,
            String name);

    private native int nativeGetNavigationHistory(long nativeContentViewCoreImpl, Object context);
    private native void nativeGetDirectedNavigationHistory(long nativeContentViewCoreImpl,
            Object context, boolean isForward, int maxEntries);
    private native String nativeGetOriginalUrlForActiveNavigationEntry(
            long nativeContentViewCoreImpl);

    private native void nativeWasResized(long nativeContentViewCoreImpl);

    private native void nativeSetAccessibilityEnabled(
            long nativeContentViewCoreImpl, boolean enabled);

    private native void nativeExtractSmartClipData(long nativeContentViewCoreImpl,
            int x, int y, int w, int h);
    private native void nativeSetBackgroundOpaque(long nativeContentViewCoreImpl, boolean opaque);

    private native void nativeResumeResponseDeferredAtStart(
            long nativeContentViewCoreImpl);
    private native void nativeSetHasPendingNavigationTransitionForTesting(
            long nativeContentViewCoreImpl);
}