Oilpan: Allocate all EventTarget derived types on the manged heap.

Source/modules/webaudio/AudioContext.h

 /*
  * Copyright (C) 2010, 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:
  * 1.  Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 58 matching lines @@
 class PannerNode;
 class PeriodicWave;
 class ScriptProcessorNode;
 class WaveShaperNode;
 
 // AudioContext is the cornerstone of the web audio API and all AudioNodes are created from it.
 // For thread safety between the audio thread and the main thread, it has a rendering graph locking mechanism.
 
 class AudioContext : public ThreadSafeRefCountedWillBeThreadSafeRefCountedGarbageCollected<AudioContext>, public ActiveDOMObject, public ScriptWrappable, public EventTargetWithInlineData {
     DEFINE_EVENT_TARGET_REFCOUNTING(ThreadSafeRefCountedWillBeThreadSafeRefCountedGarbageCollected<AudioContext>);
+    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(AudioContext);
 public:
     // Create an AudioContext for rendering to the audio hardware.
     static PassRefPtrWillBeRawPtr<AudioContext> create(Document&, ExceptionState&);
 
     virtual ~AudioContext();
 
-    virtual void trace(Visitor*);
+    virtual void trace(Visitor*) OVERRIDE;
 
     bool isInitialized() const;
     // The constructor of an AudioNode must call this to initialize the context.
     void lazyInitialize();
 
     bool isOfflineContext() { return m_isOfflineContext; }
 
     // Document notification
     virtual void stop() OVERRIDE FINAL;
     virtual bool hasPendingActivity() const OVERRIDE;
@@ skipping 225 matching lines @@
     AsyncAudioDecoder m_audioDecoder;
 
     // This is considering 32 is large enough for multiple channels audio.
     // It is somewhat arbitrary and could be increased if necessary.
     enum { MaxNumberOfChannels = 32 };
 };
 
 } // WebCore
 
 #endif // AudioContext_h