Reduce repetitive EventTarget subclassing

Source/modules/mediasource/MediaSourceBase.cpp

 /*
  * Copyright (C) 2013 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 285 matching lines @@
     event->setTarget(this);
 
     m_asyncEventQueue->enqueueEvent(event.release());
 }
 
 ScriptExecutionContext* MediaSourceBase::scriptExecutionContext() const
 {
     return ActiveDOMObject::scriptExecutionContext();
 }
 
-EventTargetData* MediaSourceBase::eventTargetData()
-{
-    return &m_eventTargetData;
-}
-
-EventTargetData* MediaSourceBase::ensureEventTargetData()
-{
-    return &m_eventTargetData;
-}
-
 URLRegistry& MediaSourceBase::registry() const
 {
     return MediaSourceRegistry::registry();
 }
 
 }