[Merge to M58] CrOS: Do not allow notifications to be added during shutdown.

chrome/browser/notifications/notification_ui_manager.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_NOTIFICATIONS_NOTIFICATION_UI_MANAGER_H_
 #define CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_UI_MANAGER_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 68 matching lines @@
   virtual bool CancelAllBySourceOrigin(const GURL& source_origin) = 0;
 
   // Removes notifications matching |profile_id|. Returns true if any were
   // removed.
   virtual bool CancelAllByProfile(ProfileID profile_id) = 0;
 
   // Cancels all pending notifications and closes anything currently showing.
   // Used when the app is terminating.
   virtual void CancelAll() = 0;
 
+  // Cancels all pending notifications and closes anything currently showing.
+  // After this is called, no new notifications can be added. Used when the app
+  // is terminating.
+  virtual void StartShutdown() = 0;
+
  protected:
   NotificationUIManager() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(NotificationUIManager);
 };
 
 #endif  // CHROME_BROWSER_NOTIFICATIONS_NOTIFICATION_UI_MANAGER_H_