[Mac] Implement the update available notification in the wrench menu.

chrome/browser/cocoa/toolbar_controller.h

Index: chrome/browser/cocoa/toolbar_controller.h
diff --git a/chrome/browser/cocoa/toolbar_controller.h b/chrome/browser/cocoa/toolbar_controller.h
index 9d3ad48906160d4ab6eff3d087803abe8a675ce5..458401a63910f2b2b2a3df5daaeb52d12715c7c6 100644
--- a/chrome/browser/cocoa/toolbar_controller.h
+++ b/chrome/browser/cocoa/toolbar_controller.h
@@ -28,7 +28,7 @@ class LocationBarViewMac;
 @class MenuButton;
 namespace ToolbarControllerInternal {
 class MenuDelegate;
-class PrefObserverBridge;
+class NotificationBridge;
 }  // namespace ToolbarControllerInternal
 class Profile;
 @class ReloadButton;
@@ -77,7 +77,7 @@ class WrenchMenuModel;
   scoped_ptr<WrenchMenuModel> wrenchMenuModel_;
 
   // Used for monitoring the optional toolbar button prefs.
-  scoped_ptr<ToolbarControllerInternal::PrefObserverBridge> prefObserver_;
+  scoped_ptr<ToolbarControllerInternal::NotificationBridge> notificationBridge_;
   BooleanPrefMember showHomeButton_;
   BooleanPrefMember showPageOptionButtons_;
   BOOL hasToolbar_;  // If NO, we may have only the location bar.