Use PrefChangeRegistrar everywhere

chrome/browser/cocoa/extensions/extension_action_context_menu.mm

 // Copyright (c) 2010 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.
 
 #import "chrome/browser/cocoa/extensions/extension_action_context_menu.h"
 
 #include "app/l10n_util_mac.h"
 #include "base/sys_string_conversions.h"
 #include "base/task.h"
 #include "chrome/browser/browser_list.h"
 #include "chrome/browser/cocoa/browser_window_cocoa.h"
 #include "chrome/browser/cocoa/browser_window_controller.h"
 #include "chrome/browser/cocoa/extensions/browser_actions_controller.h"
 #include "chrome/browser/cocoa/extensions/extension_popup_controller.h"
 #include "chrome/browser/cocoa/info_bubble_view.h"
 #import "chrome/browser/cocoa/location_bar/location_bar_view_mac.h"
 #include "chrome/browser/cocoa/toolbar_controller.h"
 #include "chrome/browser/extensions/extension_install_ui.h"
 #include "chrome/browser/extensions/extensions_service.h"
 #include "chrome/browser/extensions/extension_tabs_module.h"
+#include "chrome/browser/prefs/pref_change_registrar.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/profile.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_action.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/notification_details.h"
 #include "chrome/common/notification_observer.h"
 #include "chrome/common/notification_type.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/url_constants.h"
@@ skipping 33 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(AsyncUninstaller);
 };
 
 namespace extension_action_context_menu {
 
 class DevmodeObserver : public NotificationObserver {
  public:
   DevmodeObserver(ExtensionActionContextMenu* menu,
                              PrefService* service)
       : menu_(menu), pref_service_(service) {
-    pref_service_->AddPrefObserver(prefs::kExtensionsUIDeveloperMode,
-                                   this);
+    registrar_.Init(pref_service_);
+    registrar_.Add(prefs::kExtensionsUIDeveloperMode, this);
   }
-
-  ~DevmodeObserver() {
-    pref_service_->RemovePrefObserver(prefs::kExtensionsUIDeveloperMode,
-                                      this);
-  }
+  virtual ~DevmodeObserver() {}
 
   void Observe(NotificationType type,
                const NotificationSource& source,
                const NotificationDetails& details) {
     if (type == NotificationType::PREF_CHANGED)
       [menu_ updateInspectorItem];
     else
       NOTREACHED();
   }
 
  private:
   ExtensionActionContextMenu* menu_;
   PrefService* pref_service_;
+  PrefChangeRegistrar registrar_;
 };
 
 }  // namespace extension_action_context_menu
 
 @interface ExtensionActionContextMenu(Private)
 // Callback for the context menu items.
 - (void)dispatch:(id)menuItem;
 @end
 
 @implementation ExtensionActionContextMenu
@@ skipping 166 matching lines @@
 }
 
 - (BOOL)validateMenuItem:(NSMenuItem*)menuItem {
   if([menuItem isEqualTo:inspectorItem_.get()]) {
     return action_ && action_->HasPopup(CurrentTabId());
   }
   return YES;
 }
 
 @end