Remove the last usages of PrefObserver outside of Prefs.

chrome/browser/ui/webui/options/core_options_handler.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_WEBUI_OPTIONS_CORE_OPTIONS_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_OPTIONS_CORE_OPTIONS_HANDLER_H_
 
 #include <map>
 #include <string>
 
 #include "base/callback.h"
 #include "base/prefs/public/pref_change_registrar.h"
-#include "base/prefs/public/pref_observer.h"
 #include "base/values.h"
 #include "chrome/browser/plugins/plugin_status_pref_setter.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/ui/webui/options/options_ui.h"
 
 namespace options {
 
 // Core options UI handler.
 // Handles resource and JS calls common to all options sub-pages.
-class CoreOptionsHandler : public OptionsPageUIHandler,
-                           public PrefObserver {
+class CoreOptionsHandler : public OptionsPageUIHandler {
  public:
   CoreOptionsHandler();
   virtual ~CoreOptionsHandler();
 
   // OptionsPageUIHandler implementation.
   virtual void GetLocalizedValues(DictionaryValue* localized_strings) OVERRIDE;
   virtual void InitializeHandler() OVERRIDE;
   virtual void InitializePage() OVERRIDE;
   virtual void Uninitialize() OVERRIDE;
 
-  // PrefObserver implementation.
-  virtual void OnPreferenceChanged(PrefServiceBase* service,
-                                   const std::string& pref_name) OVERRIDE;
-
   // WebUIMessageHandler implementation.
   virtual void RegisterMessages() OVERRIDE;
 
   void set_handlers_host(OptionsPageUIHandlerHost* handlers_host) {
     handlers_host_ = handlers_host;
   }
 
   // Adds localized strings to |localized_strings|.
   static void GetStaticLocalizedValues(
       base::DictionaryValue* localized_strings);
@@ skipping 92 matching lines @@
   // value. |args| is an array of parameters as follows:
   //  item 0 - name of the preference.
   //  item 1 - name of the metric identifier (optional).
   void HandleClearPref(const ListValue* args);
 
   // Callback for the "coreOptionsUserMetricsAction" message.  This records
   // an action that should be tracked if metrics recording is enabled. |args|
   // is an array that contains a single item, the name of the metric identifier.
   void HandleUserMetricsAction(const ListValue* args);
 
+  // We need to use virtual dispatch as handling of some prefs may be
+  // finessed in subclasses.  We need to include the PrefServiceBase
+  // pointer so that subclasses can know whether we are observing the
+  // pref from the local state or not.
+  virtual void OnPreferenceChanged(PrefServiceBase* service,
+                                   const std::string& pref_name);
+
   void UpdateClearPluginLSOData();
   void UpdatePepperFlashSettingsEnabled();
 
   OptionsPageUIHandlerHost* handlers_host_;
   // This registrar keeps track of user prefs.
   PrefChangeRegistrar registrar_;
   // This registrar keeps track of local state.
   PrefChangeRegistrar local_state_registrar_;
 
   PluginStatusPrefSetter plugin_status_pref_setter_;
 
   // This maps pref names to filter functions. The callbacks should take the
   // value that the user has attempted to set for the pref, and should return
   // true if that value may be applied. If the return value is false, the
   // change will be ignored.
   typedef std::map<std::string, base::Callback<bool(const base::Value*)> >
       PrefChangeFilterMap;
   PrefChangeFilterMap pref_change_filters_;
 
   DISALLOW_COPY_AND_ASSIGN(CoreOptionsHandler);
 };
 
 }  // namespace options
 
 #endif  // CHROME_BROWSER_UI_WEBUI_OPTIONS_CORE_OPTIONS_HANDLER_H_