Make Event RefCountedGarbageCollected and implement trace() methods to the Event hierarcy

Source/modules/speech/SpeechRecognitionEvent.h

 /*
  * Copyright (C) 2012 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 copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 47 matching lines @@
     unsigned long resultIndex() const { return m_resultIndex; }
     SpeechRecognitionResultList* results() const { return m_results.get(); }
 
     // These two methods are here to satisfy the specification which requires these attrubutes to exist.
     Document* interpretation() { return 0; }
     Document* emma() { return 0; }
 
     // Event
     virtual const AtomicString& interfaceName() const OVERRIDE;
 
+    virtual void trace(Visitor*) OVERRIDE;
+
 private:
     SpeechRecognitionEvent();
     SpeechRecognitionEvent(const AtomicString&, const SpeechRecognitionEventInit&);
     SpeechRecognitionEvent(const AtomicString& eventName, unsigned long resultIndex, PassRefPtrWillBeRawPtr<SpeechRecognitionResultList> results);
 
     unsigned long m_resultIndex;
-    RefPtrWillBePersistent<SpeechRecognitionResultList> m_results;
+    RefPtrWillBeMember<SpeechRecognitionResultList> m_results;
 };
 
 } // namespace WebCore
 
 #endif // SpeechRecognitionEvent_h