Oilpan: Use transition types for HTMLMediaElement and make AudioSourceProviderClient a GC mixin.

Source/modules/webaudio/MediaStreamAudioSourceNode.h

Index: Source/modules/webaudio/MediaStreamAudioSourceNode.h
diff --git a/Source/modules/webaudio/MediaStreamAudioSourceNode.h b/Source/modules/webaudio/MediaStreamAudioSourceNode.h
index 986879799836928cdaaf989883a4d5f0f3c7e2ab..42f3f43f2fdb91ba42f4d4406c8c9b7644dbbf4b 100644
--- a/Source/modules/webaudio/MediaStreamAudioSourceNode.h
+++ b/Source/modules/webaudio/MediaStreamAudioSourceNode.h
@@ -40,6 +40,7 @@ namespace WebCore {
 class AudioContext;
 
 class MediaStreamAudioSourceNode FINAL : public AudioSourceNode, public AudioSourceProviderClient {
+    WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(MediaStreamAudioSourceNode);
 public:
     static PassRefPtrWillBeRawPtr<MediaStreamAudioSourceNode> create(AudioContext*, MediaStream*, MediaStreamTrack*, PassOwnPtr<AudioSourceProvider>);
 
@@ -55,14 +56,16 @@ public:
 
     AudioSourceProvider* audioSourceProvider() const { return m_audioSourceProvider.get(); }
 
+    virtual void trace(Visitor*) OVERRIDE;
+
 private:
     MediaStreamAudioSourceNode(AudioContext*, MediaStream*, MediaStreamTrack*, PassOwnPtr<AudioSourceProvider>);
 
     // As an audio source, we will never propagate silence.
     virtual bool propagatesSilence() const OVERRIDE { return false; }
 
-    RefPtr<MediaStream> m_mediaStream;
-    RefPtr<MediaStreamTrack> m_audioTrack;
+    RefPtrWillBeMember<MediaStream> m_mediaStream;
+    RefPtrWillBeMember<MediaStreamTrack> m_audioTrack;
     OwnPtr<AudioSourceProvider> m_audioSourceProvider;
 
     Mutex m_processLock;