[Do not commit] Track revocations in content_settings::Observer

chrome/browser/ui/webui/options/content_settings_handler.cc

 // Copyright (c) 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.
 
 #include "chrome/browser/ui/webui/options/content_settings_handler.h"
 
 #include <stddef.h>
 #include <algorithm>
 #include <map>
 #include <utility>
@@ skipping 772 matching lines @@
       ExclusiveAccessManager::IsSimplifiedFullscreenUIEnabled();
   web_ui()->CallJavascriptFunction("ContentSettings.setExclusiveAccessVisible",
                                    base::FundamentalValue(hide_settings),
                                    base::FundamentalValue(!hide_settings));
 }
 
 void ContentSettingsHandler::OnContentSettingChanged(
     const ContentSettingsPattern& primary_pattern,
     const ContentSettingsPattern& secondary_pattern,
     ContentSettingsType content_type,
+    ContentSetting previous_value,
     std::string resource_identifier) {
   const ContentSettingsDetails details(
       primary_pattern, secondary_pattern, content_type, resource_identifier);
   // TODO(estade): we pretend update_all() is always true.
   if (details.update_all_types()) {
     UpdateAllExceptionsViewsFromModel();
     UpdateAllChooserExceptionsViewsFromModel();
   } else {
     if (ContainsKey(GetExceptionsInfoMap(), details.type()))
       UpdateExceptionsViewFromModel(details.type());
@@ skipping 1048 matching lines @@
 
   // Exceptions apply only when the feature is enabled.
   PrefService* prefs = user_prefs::UserPrefs::Get(GetBrowserContext(web_ui()));
   bool enable_exceptions = prefs->GetBoolean(prefs::kEnableDRM);
   web_ui()->CallJavascriptFunction(
       "ContentSettings.enableProtectedContentExceptions",
       base::FundamentalValue(enable_exceptions));
 }
 
 }  // namespace options