Remove content::NotificationObserver dependency from most Prefs code.

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 {
+class CoreOptionsHandler
+    : public OptionsPageUIHandler,
+      public PrefObserver {
  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;
 
-  // content::NotificationObserver implementation.
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) 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(
@@ skipping 118 matching lines @@
   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_