Use ExtensionRegistryObserver instead of deprecated extension notification from c/b/e/api.

chrome/browser/extensions/api/push_messaging/push_messaging_api.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_EXTENSIONS_API_PUSH_MESSAGING_PUSH_MESSAGING_API_H__
 #define CHROME_BROWSER_EXTENSIONS_API_PUSH_MESSAGING_PUSH_MESSAGING_API_H__
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/scoped_observer.h"
 #include "chrome/browser/extensions/api/push_messaging/obfuscated_gaia_id_fetcher.h"
 #include "chrome/browser/extensions/api/push_messaging/push_messaging_invalidation_handler_delegate.h"
 #include "chrome/browser/extensions/chrome_extension_function.h"
 #include "chrome/browser/ui/webui/signin/login_ui_service.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "extensions/browser/browser_context_keyed_api_factory.h"
+#include "extensions/browser/extension_registry_observer.h"
 #include "google_apis/gaia/google_service_auth_error.h"
 #include "google_apis/gaia/oauth2_token_service.h"
 
 class Profile;
 
 namespace content {
 class BrowserContext;
 }
 
 namespace extensions {
-
+class ExtensionRegistry;
 class PushMessagingInvalidationMapper;
 
 // Observes a single InvalidationHandler and generates onMessage events.
 class PushMessagingEventRouter
     : public PushMessagingInvalidationHandlerDelegate {
  public:
   explicit PushMessagingEventRouter(Profile* profile);
   virtual ~PushMessagingEventRouter();
 
   // For testing purposes.
@@ skipping 60 matching lines @@
       const GoogleServiceAuthError& error) OVERRIDE;
 
   scoped_ptr<ObfuscatedGaiaIdFetcher> fetcher_;
   bool interactive_;
   scoped_ptr<OAuth2TokenService::Request> fetcher_access_token_request_;
 
   DISALLOW_COPY_AND_ASSIGN(PushMessagingGetChannelIdFunction);
 };
 
 class PushMessagingAPI : public BrowserContextKeyedAPI,
-                         public content::NotificationObserver {
+                         public content::NotificationObserver,
+                         public ExtensionRegistryObserver {
  public:
   explicit PushMessagingAPI(content::BrowserContext* context);
   virtual ~PushMessagingAPI();
 
   // Convenience method to get the PushMessagingAPI for a profile.
   static PushMessagingAPI* Get(content::BrowserContext* context);
 
   // KeyedService implementation.
   virtual void Shutdown() OVERRIDE;
 
@@ skipping 16 matching lines @@
   static const char* service_name() {
     return "PushMessagingAPI";
   }
   static const bool kServiceIsNULLWhileTesting = true;
 
   // content::NotificationDelegate implementation.
   virtual void Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE;
 
+  // Overridden from ExtensionRegistryObserver.
+  virtual void OnExtensionLoaded(content::BrowserContext* browser_context,
+                                 const Extension* extension) OVERRIDE;
+  virtual void OnExtensionUnloaded(
+      content::BrowserContext* browser_context,
+      const Extension* extension,
+      UnloadedExtensionInfo::Reason reason) OVERRIDE;
+
   // Created lazily when an app or extension with the push messaging permission
   // is loaded.
   scoped_ptr<PushMessagingEventRouter> event_router_;
   scoped_ptr<PushMessagingInvalidationMapper> handler_;
 
   content::NotificationRegistrar registrar_;
 
+  // Listen to extension load, unload notifications.
+  ScopedObserver<ExtensionRegistry, ExtensionRegistryObserver>
+      extension_registry_observer_;
+
   Profile* profile_;
 
   DISALLOW_COPY_AND_ASSIGN(PushMessagingAPI);
 };
 
 template <>
 void BrowserContextKeyedAPIFactory<
     PushMessagingAPI>::DeclareFactoryDependencies();
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_PUSH_MESSAGING_PUSH_MESSAGING_API_H__