Reduce repetitive EventTarget subclassing

Source/modules/mediasource/SourceBuffer.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 364 matching lines @@
 ScriptExecutionContext* SourceBuffer::scriptExecutionContext() const
 {
     return ActiveDOMObject::scriptExecutionContext();
 }
 
 const AtomicString& SourceBuffer::interfaceName() const
 {
     return eventNames().interfaceForSourceBuffer;
 }
 
-EventTargetData* SourceBuffer::eventTargetData()
-{
-    return &m_eventTargetData;
-}
-
-EventTargetData* SourceBuffer::ensureEventTargetData()
-{
-    return &m_eventTargetData;
-}
-
 bool SourceBuffer::isRemoved() const
 {
     return !m_source;
 }
 
 void SourceBuffer::scheduleEvent(const AtomicString& eventName)
 {
     ASSERT(m_asyncEventQueue);
 
     RefPtr<Event> event = Event::create(eventName);
@@ skipping 221 matching lines @@
     appendStreamDone(true);
 }
 
 void SourceBuffer::didFail(FileError::ErrorCode errorCode)
 {
     LOG(Media, "SourceBuffer::didFail(%d) %p", errorCode, this);
     appendStreamDone(false);
 }
 
 } // namespace WebCore