Moved the AppNotification system into extensions namespace

chrome/browser/extensions/app_notify_channel_ui.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_APP_NOTIFY_CHANNEL_UI_H_
 #define CHROME_BROWSER_EXTENSIONS_APP_NOTIFY_CHANNEL_UI_H_
 
 #include <string>
 
 class Profile;
 class TabContents;
 
+namespace extensions {
+
 // An interface for prompting a user to sign in to sync so that we can create
 // an app notification channel for one of their apps.
 class AppNotifyChannelUI {
  public:
   virtual ~AppNotifyChannelUI() {}
 
   // Used to customize the UI we show.
   enum UIType {
     // Do not prompt the user with an infobar.
     NO_INFOBAR,
@@ skipping 16 matching lines @@
   // instance.
   virtual void PromptSyncSetup(Delegate* delegate) = 0;
 
   // Builds the platform specific AppNotifyChannelUI.
   static AppNotifyChannelUI* Create(Profile* profile,
                                     TabContents* tab_contents,
                                     const std::string& app_name,
                                     AppNotifyChannelUI::UIType ui_type);
 };
 
+}  // namespace extensions
+
 #endif  // CHROME_BROWSER_EXTENSIONS_APP_NOTIFY_CHANNEL_UI_H_