Oilpan: remove RawPtr<> usage for WebNotification.

Source/web/WebNotification.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 96 matching lines @@
 {
     // FIXME: byUser flag not supported by WebCore yet
     m_private->dispatchCloseEvent();
 }
 
 void WebNotification::dispatchClickEvent()
 {
     m_private->dispatchClickEvent();
 }
 
-WebNotification::WebNotification(const WTF::RawPtr<Notification>& notification)
+WebNotification::WebNotification(Notification* notification)
     : m_private(notification)
 {
 }
 
-WebNotification& WebNotification::operator=(const WTF::RawPtr<Notification>& notification)
+WebNotification& WebNotification::operator=(Notification* notification)
 {
     m_private = notification;
     return *this;
 }
 
 } // namespace blink