Tried to move AudioSummingJuction to oilpan

Source/modules/webaudio/AudioSummingJunction.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:
  * 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
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
  * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef AudioSummingJunction_h
 #define AudioSummingJunction_h
 
 #include "platform/audio/AudioBus.h"
+#include "platform/heap/Handle.h"
 #include "wtf/HashSet.h"
 #include "wtf/Vector.h"
 
 namespace WebCore {
 
 class AudioContext;
 class AudioNodeOutput;
 
 // An AudioSummingJunction represents a point where zero, one, or more AudioNodeOutputs connect.
 
-class AudioSummingJunction {
+class AudioSummingJunction : public RefCountedWillBeGarbageCollected<AudioSummingJunction> {
 public:
     explicit AudioSummingJunction(AudioContext*);
-    virtual ~AudioSummingJunction();
 
     // Can be called from any thread.
     AudioContext* context() { return m_context.get(); }
 
     // This must be called whenever we modify m_outputs.
     void changedOutputs();
 
     // This copies m_outputs to m_renderingOutputs. Please see comments for these lists below.
     // This must be called when we own the context's graph lock in the audio thread at the very start or end of the render quantum.
     void updateRenderingState();
 
     // Rendering code accesses its version of the current connections here.
     unsigned numberOfRenderingConnections() const { return m_renderingOutputs.size(); }
     AudioNodeOutput* renderingOutput(unsigned i) { return m_renderingOutputs[i]; }
     bool isConnected() const { return numberOfRenderingConnections() > 0; }
 
     virtual bool canUpdateState() = 0;
     virtual void didUpdate() = 0;
 
+    virtual void trace(Visitor*);
+
 protected:
-    RefPtr<AudioContext> m_context;
+    RefPtrWillBeMember<AudioContext> m_context;
 
     // m_outputs contains the AudioNodeOutputs representing current connections which are not disabled.
     // The rendering code should never use this directly, but instead uses m_renderingOutputs.
     HashSet<AudioNodeOutput*> m_outputs;
 
     // m_renderingOutputs is a copy of m_outputs which will never be modified during the graph rendering on the audio thread.
     // This is the list which is used by the rendering code.
     // Whenever m_outputs is modified, the context is told so it can later update m_renderingOutputs from m_outputs at a safe time.
     // Most of the time, m_renderingOutputs is identical to m_outputs.
     Vector<AudioNodeOutput*> m_renderingOutputs;
 
     // m_renderingStateNeedUpdating keeps track if m_outputs is modified.
     bool m_renderingStateNeedUpdating;
 };
 
 } // namespace WebCore
 
 #endif // AudioSummingJunction_h