Hide the process of instantiating NotificationServiceImpl from embedders.

content/public/browser/notification_service.h

 // Copyright (c) 2011 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.
 
 // This file describes a central switchboard for notifications that might
 // happen in various parts of the application, and allows users to register
 // observers for various classes of events that they're interested in.
 
 #ifndef CONTENT_PUBLIC_BROWSER_NOTIFICATION_SERVICE_H_
 #define CONTENT_PUBLIC_BROWSER_NOTIFICATION_SERVICE_H_
 #pragma once
 
 #include "content/common/content_export.h"
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_source.h"
 
 namespace content {
 
 class CONTENT_EXPORT NotificationService {
  public:
   // Returns the NotificationService object for the current thread, or NULL if
   // none.
   static NotificationService* current();
 
+  static NotificationService* Create();
+
   virtual ~NotificationService() {}
 
   // Synchronously posts a notification to all interested observers.
   // Source is a reference to a NotificationSource object representing
   // the object originating the notification (can be
   // NotificationService::AllSources(), in which case
   // only observers interested in all sources will be notified).
   // Details is a reference to an object containing additional data about
   // the notification.  If no additional data is needed, NoDetails() is used.
   // There is no particular order in which the observers will be notified.
@@ skipping 20 matching lines @@
   }
 
   // Returns a NotificationDetails object that represents a lack of details
   // associated with a notification.  (This is effectively a null pointer.)
   static Details<void> NoDetails() { return Details<void>(NULL); }
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_NOTIFICATION_SERVICE_H_