prefs_tab_helper.cc revision 03b57e008b61dfcb1fbad3aea950ae0e001748b0 
1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "chrome/browser/ui/prefs/prefs_tab_helper.h"
6
7#include <string>
8
9#include "base/prefs/overlay_user_pref_store.h"
10#include "base/prefs/pref_service.h"
11#include "base/strings/string_util.h"
12#include "base/strings/stringprintf.h"
13#include "base/strings/utf_string_conversions.h"
14#include "chrome/browser/browser_process.h"
15#include "chrome/browser/chrome_notification_types.h"
16#include "chrome/browser/profiles/profile.h"
17#include "chrome/browser/renderer_preferences_util.h"
18#include "chrome/common/pref_font_webkit_names.h"
19#include "chrome/common/pref_names.h"
20#include "chrome/common/pref_names_util.h"
21#include "components/pref_registry/pref_registry_syncable.h"
22#include "content/public/browser/notification_details.h"
23#include "content/public/browser/notification_service.h"
24#include "content/public/browser/render_view_host.h"
25#include "content/public/browser/web_contents.h"
26#include "content/public/common/web_preferences.h"
27#include "grit/locale_settings.h"
28#include "grit/platform_locale_settings.h"
29#include "third_party/icu/source/common/unicode/uchar.h"
30#include "third_party/icu/source/common/unicode/uscript.h"
31#include "ui/base/l10n/l10n_util.h"
32
33#if defined(OS_POSIX) && !defined(OS_MACOSX) && defined(ENABLE_THEMES)
34#include "chrome/browser/themes/theme_service.h"
35#include "chrome/browser/themes/theme_service_factory.h"
36#endif
37
38#if defined(OS_WIN)
39#include "base/win/windows_version.h"
40#endif
41
42using content::WebContents;
43using content::WebPreferences;
44
45DEFINE_WEB_CONTENTS_USER_DATA_KEY(PrefsTabHelper);
46
47namespace {
48
49// The list of prefs we want to observe.
50const char* kPrefsToObserve[] = {
51  prefs::kDefaultCharset,
52  prefs::kDisable3DAPIs,
53  prefs::kEnableHyperlinkAuditing,
54  prefs::kWebKitAllowDisplayingInsecureContent,
55  prefs::kWebKitAllowRunningInsecureContent,
56  prefs::kWebKitDefaultFixedFontSize,
57  prefs::kWebKitDefaultFontSize,
58  prefs::kWebKitDomPasteEnabled,
59#if defined(OS_ANDROID)
60  prefs::kWebKitFontScaleFactor,
61  prefs::kWebKitForceEnableZoom,
62  prefs::kWebKitPasswordEchoEnabled,
63#endif
64  prefs::kWebKitJavascriptCanOpenWindowsAutomatically,
65  prefs::kWebKitJavascriptEnabled,
66  prefs::kWebKitJavaEnabled,
67  prefs::kWebKitLoadsImagesAutomatically,
68  prefs::kWebKitMinimumFontSize,
69  prefs::kWebKitMinimumLogicalFontSize,
70  prefs::kWebKitPluginsEnabled,
71  prefs::kWebKitShrinksStandaloneImagesToFit,
72  prefs::kWebkitTabsToLinks,
73  prefs::kWebKitTextAreasAreResizable,
74  prefs::kWebKitUsesUniversalDetector,
75  prefs::kWebKitWebSecurityEnabled,
76};
77
78const int kPrefsToObserveLength = arraysize(kPrefsToObserve);
79
80#if !defined(OS_ANDROID)
81// Registers a preference under the path |pref_name| for each script used for
82// per-script font prefs.
83// For example, for WEBKIT_WEBPREFS_FONTS_SERIF ("fonts.serif"):
84// "fonts.serif.Arab", "fonts.serif.Hang", etc. are registered.
85// |fonts_with_defaults| contains all |pref_names| already registered since they
86// have a specified default value.
87// On Android there are no default values for these properties and there is no
88// way to set them (because extensions are not supported so the Font Settings
89// API cannot be used), so we can avoid registering them altogether.
90void RegisterFontFamilyPrefs(user_prefs::PrefRegistrySyncable* registry,
91                             const std::set<std::string>& fonts_with_defaults) {
92
93  // Expand the font concatenated with script name so this stays at RO memory
94  // rather than allocated in heap.
95  static const char* const kFontFamilyMap[] = {
96#define EXPAND_SCRIPT_FONT(map_name, script_name) map_name "." script_name,
97
98#include "chrome/common/pref_font_script_names-inl.h"
99ALL_FONT_SCRIPTS(WEBKIT_WEBPREFS_FONTS_CURSIVE)
100ALL_FONT_SCRIPTS(WEBKIT_WEBPREFS_FONTS_FANTASY)
101ALL_FONT_SCRIPTS(WEBKIT_WEBPREFS_FONTS_FIXED)
102ALL_FONT_SCRIPTS(WEBKIT_WEBPREFS_FONTS_PICTOGRAPH)
103ALL_FONT_SCRIPTS(WEBKIT_WEBPREFS_FONTS_SANSERIF)
104ALL_FONT_SCRIPTS(WEBKIT_WEBPREFS_FONTS_SERIF)
105ALL_FONT_SCRIPTS(WEBKIT_WEBPREFS_FONTS_STANDARD)
106
107#undef EXPAND_SCRIPT_FONT
108  };
109
110  for (size_t i = 0; i < arraysize(kFontFamilyMap); ++i) {
111    const char* pref_name = kFontFamilyMap[i];
112    if (fonts_with_defaults.find(pref_name) == fonts_with_defaults.end()) {
113      // We haven't already set a default value for this font preference, so set
114      // an empty string as the default.
115      registry->RegisterStringPref(
116          pref_name,
117          std::string(),
118          user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
119    }
120  }
121}
122#endif  // !defined(OS_ANDROID)
123
124// Registers |obs| to observe per-script font prefs under the path |map_name|.
125// On android, there's no exposed way to change these prefs, so we can save
126// ~715KB of heap and some startup cycles by avoiding observing these prefs
127// since they will never change.
128void RegisterFontFamilyMapObserver(
129    PrefChangeRegistrar* registrar,
130    const char* map_name,
131    const PrefChangeRegistrar::NamedChangeCallback& obs) {
132  DCHECK(StartsWithASCII(map_name, "webkit.webprefs.", true));
133  for (size_t i = 0; i < prefs::kWebKitScriptsForFontFamilyMapsLength; ++i) {
134    const char* script = prefs::kWebKitScriptsForFontFamilyMaps[i];
135    std::string pref_name = base::StringPrintf("%s.%s", map_name, script);
136    registrar->Add(pref_name.c_str(), obs);
137  }
138}
139
140#if defined(OS_WIN)
141// On Windows with antialising we want to use an alternate fixed font like
142// Consolas, which looks much better than Courier New.
143bool ShouldUseAlternateDefaultFixedFont(const std::string& script) {
144  if (!StartsWithASCII(script, "courier", false))
145    return false;
146  UINT smooth_type = 0;
147  SystemParametersInfo(SPI_GETFONTSMOOTHINGTYPE, 0, &smooth_type, 0);
148  return (base::win::GetVersion() >= base::win::VERSION_WIN7) &&
149         (smooth_type == FE_FONTSMOOTHINGCLEARTYPE);
150}
151#endif
152
153struct FontDefault {
154  const char* pref_name;
155  int resource_id;
156};
157
158// Font pref defaults.  The prefs that have defaults vary by platform, since not
159// all platforms have fonts for all scripts for all generic families.
160// TODO(falken): add proper defaults when possible for all
161// platforms/scripts/generic families.
162const FontDefault kFontDefaults[] = {
163  { prefs::kWebKitStandardFontFamily, IDS_STANDARD_FONT_FAMILY },
164  { prefs::kWebKitFixedFontFamily, IDS_FIXED_FONT_FAMILY },
165  { prefs::kWebKitSerifFontFamily, IDS_SERIF_FONT_FAMILY },
166  { prefs::kWebKitSansSerifFontFamily, IDS_SANS_SERIF_FONT_FAMILY },
167  { prefs::kWebKitCursiveFontFamily, IDS_CURSIVE_FONT_FAMILY },
168  { prefs::kWebKitFantasyFontFamily, IDS_FANTASY_FONT_FAMILY },
169  { prefs::kWebKitPictographFontFamily, IDS_PICTOGRAPH_FONT_FAMILY },
170#if defined(OS_CHROMEOS) || defined(OS_MACOSX) || defined(OS_WIN)
171  { prefs::kWebKitStandardFontFamilyJapanese,
172    IDS_STANDARD_FONT_FAMILY_JAPANESE },
173  { prefs::kWebKitFixedFontFamilyJapanese, IDS_FIXED_FONT_FAMILY_JAPANESE },
174  { prefs::kWebKitSerifFontFamilyJapanese, IDS_SERIF_FONT_FAMILY_JAPANESE },
175  { prefs::kWebKitSansSerifFontFamilyJapanese,
176    IDS_SANS_SERIF_FONT_FAMILY_JAPANESE },
177  { prefs::kWebKitStandardFontFamilyKorean, IDS_STANDARD_FONT_FAMILY_KOREAN },
178  { prefs::kWebKitSerifFontFamilyKorean, IDS_SERIF_FONT_FAMILY_KOREAN },
179  { prefs::kWebKitSansSerifFontFamilyKorean,
180    IDS_SANS_SERIF_FONT_FAMILY_KOREAN },
181  { prefs::kWebKitStandardFontFamilySimplifiedHan,
182    IDS_STANDARD_FONT_FAMILY_SIMPLIFIED_HAN },
183  { prefs::kWebKitSerifFontFamilySimplifiedHan,
184    IDS_SERIF_FONT_FAMILY_SIMPLIFIED_HAN },
185  { prefs::kWebKitSansSerifFontFamilySimplifiedHan,
186    IDS_SANS_SERIF_FONT_FAMILY_SIMPLIFIED_HAN },
187  { prefs::kWebKitStandardFontFamilyTraditionalHan,
188    IDS_STANDARD_FONT_FAMILY_TRADITIONAL_HAN },
189  { prefs::kWebKitSerifFontFamilyTraditionalHan,
190    IDS_SERIF_FONT_FAMILY_TRADITIONAL_HAN },
191  { prefs::kWebKitSansSerifFontFamilyTraditionalHan,
192    IDS_SANS_SERIF_FONT_FAMILY_TRADITIONAL_HAN },
193#endif
194#if defined(OS_CHROMEOS)
195  { prefs::kWebKitStandardFontFamilyArabic, IDS_STANDARD_FONT_FAMILY_ARABIC },
196  { prefs::kWebKitSerifFontFamilyArabic, IDS_SERIF_FONT_FAMILY_ARABIC },
197  { prefs::kWebKitSansSerifFontFamilyArabic,
198    IDS_SANS_SERIF_FONT_FAMILY_ARABIC },
199  { prefs::kWebKitFixedFontFamilyKorean, IDS_FIXED_FONT_FAMILY_KOREAN },
200  { prefs::kWebKitFixedFontFamilySimplifiedHan,
201    IDS_FIXED_FONT_FAMILY_SIMPLIFIED_HAN },
202  { prefs::kWebKitFixedFontFamilyTraditionalHan,
203    IDS_FIXED_FONT_FAMILY_TRADITIONAL_HAN },
204#elif defined(OS_WIN)
205  { prefs::kWebKitStandardFontFamilyCyrillic,
206    IDS_STANDARD_FONT_FAMILY_CYRILLIC },
207  { prefs::kWebKitFixedFontFamilyCyrillic, IDS_FIXED_FONT_FAMILY_CYRILLIC },
208  { prefs::kWebKitSerifFontFamilyCyrillic, IDS_SERIF_FONT_FAMILY_CYRILLIC },
209  { prefs::kWebKitSansSerifFontFamilyCyrillic,
210    IDS_SANS_SERIF_FONT_FAMILY_CYRILLIC },
211  { prefs::kWebKitStandardFontFamilyGreek, IDS_STANDARD_FONT_FAMILY_GREEK },
212  { prefs::kWebKitFixedFontFamilyGreek, IDS_FIXED_FONT_FAMILY_GREEK },
213  { prefs::kWebKitSerifFontFamilyGreek, IDS_SERIF_FONT_FAMILY_GREEK },
214  { prefs::kWebKitSansSerifFontFamilyGreek, IDS_SANS_SERIF_FONT_FAMILY_GREEK },
215  { prefs::kWebKitFixedFontFamilyKorean, IDS_FIXED_FONT_FAMILY_KOREAN },
216  { prefs::kWebKitCursiveFontFamilyKorean, IDS_CURSIVE_FONT_FAMILY_KOREAN },
217  { prefs::kWebKitFixedFontFamilySimplifiedHan,
218    IDS_FIXED_FONT_FAMILY_SIMPLIFIED_HAN },
219  { prefs::kWebKitFixedFontFamilyTraditionalHan,
220    IDS_FIXED_FONT_FAMILY_TRADITIONAL_HAN },
221#endif
222};
223
224const size_t kFontDefaultsLength = arraysize(kFontDefaults);
225
226// Returns the script of the font pref |pref_name|.  For example, suppose
227// |pref_name| is "webkit.webprefs.fonts.serif.Hant".  Since the script code for
228// the script name "Hant" is USCRIPT_TRADITIONAL_HAN, the function returns
229// USCRIPT_TRADITIONAL_HAN.  |pref_name| must be a valid font pref name.
230UScriptCode GetScriptOfFontPref(const char* pref_name) {
231  // ICU script names are four letters.
232  static const size_t kScriptNameLength = 4;
233
234  size_t len = strlen(pref_name);
235  DCHECK_GT(len, kScriptNameLength);
236  const char* scriptName = &pref_name[len - kScriptNameLength];
237  int32 code = u_getPropertyValueEnum(UCHAR_SCRIPT, scriptName);
238  DCHECK(code >= 0 && code < USCRIPT_CODE_LIMIT);
239  return static_cast<UScriptCode>(code);
240}
241
242// If |scriptCode| is a member of a family of "similar" script codes, returns
243// the script code in that family that is used in font pref names.  For example,
244// USCRIPT_HANGUL and USCRIPT_KOREAN are considered equivalent for the purposes
245// of font selection.  Chrome uses the script code USCRIPT_HANGUL (script name
246// "Hang") in Korean font pref names (for example,
247// "webkit.webprefs.fonts.serif.Hang").  So, if |scriptCode| is USCRIPT_KOREAN,
248// the function returns USCRIPT_HANGUL.  If |scriptCode| is not a member of such
249// a family, returns |scriptCode|.
250UScriptCode GetScriptForFontPrefMatching(UScriptCode scriptCode) {
251  switch (scriptCode) {
252  case USCRIPT_HIRAGANA:
253  case USCRIPT_KATAKANA:
254  case USCRIPT_KATAKANA_OR_HIRAGANA:
255    return USCRIPT_JAPANESE;
256  case USCRIPT_KOREAN:
257    return USCRIPT_HANGUL;
258  default:
259    return scriptCode;
260  }
261}
262
263// Returns the primary script used by the browser's UI locale.  For example, if
264// the locale is "ru", the function returns USCRIPT_CYRILLIC, and if the locale
265// is "en", the function returns USCRIPT_LATIN.
266UScriptCode GetScriptOfBrowserLocale() {
267  std::string locale = g_browser_process->GetApplicationLocale();
268
269  // For Chinese locales, uscript_getCode() just returns USCRIPT_HAN but our
270  // per-script fonts are for USCRIPT_SIMPLIFIED_HAN and
271  // USCRIPT_TRADITIONAL_HAN.
272  if (locale == "zh-CN")
273    return USCRIPT_SIMPLIFIED_HAN;
274  if (locale == "zh-TW")
275    return USCRIPT_TRADITIONAL_HAN;
276
277  UScriptCode code = USCRIPT_INVALID_CODE;
278  UErrorCode err = U_ZERO_ERROR;
279  uscript_getCode(locale.c_str(), &code, 1, &err);
280
281  // Ignore the error that multiple scripts could be returned, since we only
282  // want one script.
283  if (U_FAILURE(err) && err != U_BUFFER_OVERFLOW_ERROR)
284    code = USCRIPT_INVALID_CODE;
285  return GetScriptForFontPrefMatching(code);
286}
287
288// Sets a font family pref in |prefs| to |pref_value|.
289void OverrideFontFamily(WebPreferences* prefs,
290                        const std::string& generic_family,
291                        const std::string& script,
292                        const std::string& pref_value) {
293  content::ScriptFontFamilyMap* map = NULL;
294  if (generic_family == "standard")
295    map = &prefs->standard_font_family_map;
296  else if (generic_family == "fixed")
297    map = &prefs->fixed_font_family_map;
298  else if (generic_family == "serif")
299    map = &prefs->serif_font_family_map;
300  else if (generic_family == "sansserif")
301    map = &prefs->sans_serif_font_family_map;
302  else if (generic_family == "cursive")
303    map = &prefs->cursive_font_family_map;
304  else if (generic_family == "fantasy")
305    map = &prefs->fantasy_font_family_map;
306  else if (generic_family == "pictograph")
307    map = &prefs->pictograph_font_family_map;
308  else
309    NOTREACHED() << "Unknown generic font family: " << generic_family;
310  (*map)[script] = base::UTF8ToUTF16(pref_value);
311}
312
313}  // namespace
314
315PrefsTabHelper::PrefsTabHelper(WebContents* contents)
316    : web_contents_(contents),
317      weak_ptr_factory_(this) {
318  PrefService* prefs = GetProfile()->GetPrefs();
319  pref_change_registrar_.Init(prefs);
320  if (prefs) {
321    base::Closure renderer_callback = base::Bind(
322        &PrefsTabHelper::UpdateRendererPreferences, base::Unretained(this));
323    pref_change_registrar_.Add(prefs::kAcceptLanguages, renderer_callback);
324    pref_change_registrar_.Add(prefs::kDefaultZoomLevel, renderer_callback);
325    pref_change_registrar_.Add(prefs::kEnableDoNotTrack, renderer_callback);
326    pref_change_registrar_.Add(prefs::kEnableReferrers, renderer_callback);
327
328#if !defined(OS_MACOSX)
329    pref_change_registrar_.Add(prefs::kFullscreenAllowed, renderer_callback);
330#endif
331
332    PrefChangeRegistrar::NamedChangeCallback webkit_callback = base::Bind(
333        &PrefsTabHelper::OnWebPrefChanged, base::Unretained(this));
334    for (int i = 0; i < kPrefsToObserveLength; ++i) {
335      const char* pref_name = kPrefsToObserve[i];
336      pref_change_registrar_.Add(pref_name, webkit_callback);
337    }
338
339    RegisterFontFamilyMapObserver(&pref_change_registrar_,
340                                  prefs::kWebKitStandardFontFamilyMap,
341                                  webkit_callback);
342    RegisterFontFamilyMapObserver(&pref_change_registrar_,
343                                  prefs::kWebKitFixedFontFamilyMap,
344                                  webkit_callback);
345    RegisterFontFamilyMapObserver(&pref_change_registrar_,
346                                  prefs::kWebKitSerifFontFamilyMap,
347                                  webkit_callback);
348    RegisterFontFamilyMapObserver(&pref_change_registrar_,
349                                  prefs::kWebKitSansSerifFontFamilyMap,
350                                  webkit_callback);
351    RegisterFontFamilyMapObserver(&pref_change_registrar_,
352                                  prefs::kWebKitCursiveFontFamilyMap,
353                                  webkit_callback);
354    RegisterFontFamilyMapObserver(&pref_change_registrar_,
355                                  prefs::kWebKitFantasyFontFamilyMap,
356                                  webkit_callback);
357    RegisterFontFamilyMapObserver(&pref_change_registrar_,
358                                  prefs::kWebKitPictographFontFamilyMap,
359                                  webkit_callback);
360  }
361
362  renderer_preferences_util::UpdateFromSystemSettings(
363      web_contents_->GetMutableRendererPrefs(), GetProfile());
364
365#if defined(OS_POSIX) && !defined(OS_MACOSX) && defined(ENABLE_THEMES)
366  registrar_.Add(this, chrome::NOTIFICATION_BROWSER_THEME_CHANGED,
367                 content::Source<ThemeService>(
368                     ThemeServiceFactory::GetForProfile(GetProfile())));
369#endif
370#if defined(USE_AURA)
371  registrar_.Add(this,
372                 chrome::NOTIFICATION_BROWSER_FLING_CURVE_PARAMETERS_CHANGED,
373                 content::NotificationService::AllSources());
374#endif
375}
376
377PrefsTabHelper::~PrefsTabHelper() {
378}
379
380// static
381void PrefsTabHelper::InitIncognitoUserPrefStore(
382    OverlayUserPrefStore* pref_store) {
383  // List of keys that cannot be changed in the user prefs file by the incognito
384  // profile.  All preferences that store information about the browsing history
385  // or behavior of the user should have this property.
386  pref_store->RegisterOverlayPref(prefs::kBrowserWindowPlacement);
387  pref_store->RegisterOverlayPref(prefs::kSaveFileDefaultDirectory);
388#if defined(OS_ANDROID) || defined(OS_IOS)
389  pref_store->RegisterOverlayPref(prefs::kProxy);
390#endif  // defined(OS_ANDROID) || defined(OS_IOS)
391}
392
393// static
394void PrefsTabHelper::RegisterProfilePrefs(
395    user_prefs::PrefRegistrySyncable* registry) {
396  WebPreferences pref_defaults;
397  registry->RegisterBooleanPref(
398      prefs::kWebKitJavascriptEnabled,
399      pref_defaults.javascript_enabled,
400      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
401  registry->RegisterBooleanPref(
402      prefs::kWebKitWebSecurityEnabled,
403      pref_defaults.web_security_enabled,
404      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
405  registry->RegisterBooleanPref(
406      prefs::kWebKitJavascriptCanOpenWindowsAutomatically,
407      true,
408      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
409  registry->RegisterBooleanPref(
410      prefs::kWebKitLoadsImagesAutomatically,
411      pref_defaults.loads_images_automatically,
412      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
413  registry->RegisterBooleanPref(
414      prefs::kWebKitPluginsEnabled,
415      pref_defaults.plugins_enabled,
416      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
417  registry->RegisterBooleanPref(
418      prefs::kWebKitDomPasteEnabled,
419      pref_defaults.dom_paste_enabled,
420      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
421  registry->RegisterBooleanPref(
422      prefs::kWebKitShrinksStandaloneImagesToFit,
423      pref_defaults.shrinks_standalone_images_to_fit,
424      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
425  registry->RegisterBooleanPref(
426      prefs::kWebKitTextAreasAreResizable,
427      pref_defaults.text_areas_are_resizable,
428      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
429  registry->RegisterBooleanPref(
430      prefs::kWebKitJavaEnabled,
431      pref_defaults.java_enabled,
432      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
433  registry->RegisterBooleanPref(
434      prefs::kWebkitTabsToLinks,
435      pref_defaults.tabs_to_links,
436      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
437  registry->RegisterBooleanPref(
438      prefs::kWebKitAllowRunningInsecureContent,
439      false,
440      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
441  registry->RegisterBooleanPref(
442      prefs::kWebKitAllowDisplayingInsecureContent,
443      true,
444      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
445  registry->RegisterBooleanPref(
446      prefs::kEnableReferrers,
447      true,
448      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
449#if defined(OS_ANDROID)
450  registry->RegisterDoublePref(
451      prefs::kWebKitFontScaleFactor,
452      1.0,
453      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
454  registry->RegisterBooleanPref(
455      prefs::kWebKitForceEnableZoom,
456      pref_defaults.force_enable_zoom,
457      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
458  registry->RegisterBooleanPref(
459      prefs::kWebKitPasswordEchoEnabled,
460      pref_defaults.password_echo_enabled,
461      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
462#endif
463  registry->RegisterLocalizedStringPref(
464      prefs::kAcceptLanguages,
465      IDS_ACCEPT_LANGUAGES,
466      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
467  registry->RegisterLocalizedStringPref(
468      prefs::kDefaultCharset,
469      IDS_DEFAULT_ENCODING,
470      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
471
472  // Register font prefs that have defaults.
473  std::set<std::string> fonts_with_defaults;
474  UScriptCode browser_script = GetScriptOfBrowserLocale();
475  for (size_t i = 0; i < kFontDefaultsLength; ++i) {
476    FontDefault pref = kFontDefaults[i];
477
478#if defined(OS_WIN)
479    if (pref.pref_name == prefs::kWebKitFixedFontFamily) {
480      if (ShouldUseAlternateDefaultFixedFont(
481              l10n_util::GetStringUTF8(pref.resource_id)))
482        pref.resource_id = IDS_FIXED_FONT_FAMILY_ALT_WIN;
483    }
484#endif
485
486    UScriptCode pref_script = GetScriptOfFontPref(pref.pref_name);
487
488    // Suppress this default font pref value if it is for the primary script of
489    // the browser's UI locale.  For example, if the pref is for the sans-serif
490    // font for the Cyrillic script, and the browser locale is "ru" (Russian),
491    // the default is suppressed.  Otherwise, the default would override the
492    // user's font preferences when viewing pages in their native language.
493    // This is because users have no way yet of customizing their per-script
494    // font preferences.  The font prefs accessible in the options UI are for
495    // the default, unknown script; these prefs have less priority than the
496    // per-script font prefs when the script of the content is known.  This code
497    // can possibly be removed later if users can easily access per-script font
498    // prefs (e.g., via the extensions workflow), or the problem turns out to
499    // not be really critical after all.
500    if (browser_script != pref_script) {
501      registry->RegisterLocalizedStringPref(
502          pref.pref_name,
503          pref.resource_id,
504          user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
505      fonts_with_defaults.insert(pref.pref_name);
506    }
507  }
508
509  // Register per-script font prefs that don't have defaults.
510#if !defined(OS_ANDROID)
511  RegisterFontFamilyPrefs(registry, fonts_with_defaults);
512#endif
513
514  registry->RegisterLocalizedIntegerPref(
515      prefs::kWebKitDefaultFontSize,
516      IDS_DEFAULT_FONT_SIZE,
517      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
518  registry->RegisterLocalizedIntegerPref(
519      prefs::kWebKitDefaultFixedFontSize,
520      IDS_DEFAULT_FIXED_FONT_SIZE,
521      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
522  registry->RegisterLocalizedIntegerPref(
523      prefs::kWebKitMinimumFontSize,
524      IDS_MINIMUM_FONT_SIZE,
525      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
526  registry->RegisterLocalizedIntegerPref(
527      prefs::kWebKitMinimumLogicalFontSize,
528      IDS_MINIMUM_LOGICAL_FONT_SIZE,
529      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
530  registry->RegisterLocalizedBooleanPref(
531      prefs::kWebKitUsesUniversalDetector,
532      IDS_USES_UNIVERSAL_DETECTOR,
533      user_prefs::PrefRegistrySyncable::SYNCABLE_PREF);
534  registry->RegisterLocalizedStringPref(
535      prefs::kStaticEncodings,
536      IDS_STATIC_ENCODING_LIST,
537      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
538  registry->RegisterStringPref(
539      prefs::kRecentlySelectedEncoding,
540      std::string(),
541      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
542}
543
544void PrefsTabHelper::Observe(int type,
545                             const content::NotificationSource& source,
546                             const content::NotificationDetails& details) {
547#if defined(OS_POSIX) && !defined(OS_MACOSX) && defined(ENABLE_THEMES)
548  if (type == chrome::NOTIFICATION_BROWSER_THEME_CHANGED) {
549    UpdateRendererPreferences();
550    return;
551  }
552#endif
553
554#if defined(USE_AURA)
555  if (type == chrome::NOTIFICATION_BROWSER_FLING_CURVE_PARAMETERS_CHANGED) {
556    UpdateRendererPreferences();
557    return;
558  }
559#endif  // defined(USE_AURA)
560
561  NOTREACHED();
562}
563
564void PrefsTabHelper::UpdateWebPreferences() {
565  web_contents_->GetRenderViewHost()->UpdateWebkitPreferences(
566      web_contents_->GetRenderViewHost()->GetWebkitPreferences());
567}
568
569void PrefsTabHelper::UpdateRendererPreferences() {
570  renderer_preferences_util::UpdateFromSystemSettings(
571      web_contents_->GetMutableRendererPrefs(), GetProfile());
572  web_contents_->GetRenderViewHost()->SyncRendererPrefs();
573}
574
575Profile* PrefsTabHelper::GetProfile() {
576  return Profile::FromBrowserContext(web_contents_->GetBrowserContext());
577}
578
579void PrefsTabHelper::OnFontFamilyPrefChanged(const std::string& pref_name) {
580  // When a font family pref's value goes from non-empty to the empty string, we
581  // must add it to the usual WebPreferences struct passed to the renderer.
582  //
583  // The empty string means to fall back to the pref for the Common script
584  // ("Zyyy").  For example, if chrome.fonts.serif.Cyrl is the empty string, it
585  // means to use chrome.fonts.serif.Zyyy for Cyrillic script. Prefs that are
586  // the empty string are normally not passed to WebKit, since there are so many
587  // of them that it would cause a performance regression. Not passing the pref
588  // is normally okay since WebKit does the desired fallback behavior regardless
589  // of whether the empty string is passed or the pref is not passed at all. But
590  // if the pref has changed from non-empty to the empty string, we must let
591  // WebKit know.
592  std::string generic_family;
593  std::string script;
594  if (pref_names_util::ParseFontNamePrefPath(pref_name,
595                                             &generic_family,
596                                             &script)) {
597    PrefService* prefs = GetProfile()->GetPrefs();
598    std::string pref_value = prefs->GetString(pref_name.c_str());
599    if (pref_value.empty()) {
600      WebPreferences web_prefs =
601          web_contents_->GetRenderViewHost()->GetWebkitPreferences();
602      OverrideFontFamily(&web_prefs, generic_family, script, std::string());
603      web_contents_->GetRenderViewHost()->UpdateWebkitPreferences(web_prefs);
604      return;
605    }
606  }
607}
608
609void PrefsTabHelper::OnWebPrefChanged(const std::string& pref_name) {
610#if !defined(OS_ANDROID)
611  OnFontFamilyPrefChanged(pref_name);
612#endif
613
614  web_contents_->GetRenderViewHost()->OnWebkitPreferencesChanged();
615}
616