Make IDL Callbacks non-refcounted by default

Source/modules/webaudio/AsyncAudioDecoder.h

 /*
  * Copyright (C) 2011, 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 26 matching lines @@
 // AsyncAudioDecoder asynchronously decodes audio file data from an ArrayBuffer in a worker thread.
 // Upon successful decoding, a completion callback will be invoked with the decoded PCM data in an AudioBuffer.
 
 class AsyncAudioDecoder {
     WTF_MAKE_NONCOPYABLE(AsyncAudioDecoder);
 public:
     AsyncAudioDecoder();
     ~AsyncAudioDecoder();
 
     // Must be called on the main thread.
-    void decodeAsync(ArrayBuffer* audioData, float sampleRate, PassRefPtr<AudioBufferCallback> successCallback, PassRefPtr<AudioBufferCallback> errorCallback);
+    void decodeAsync(ArrayBuffer* audioData, float sampleRate, PassOwnPtr<AudioBufferCallback> successCallback, PassOwnPtr<AudioBufferCallback> errorCallback);
 
 private:
     static void decode(ArrayBuffer* audioData, float sampleRate, AudioBufferCallback* successCallback, AudioBufferCallback* errorCallback);
     static void notifyComplete(ArrayBuffer* audioData, AudioBufferCallback* successCallback, AudioBufferCallback* errorCallback, AudioBuffer*);
 
     OwnPtr<blink::WebThread> m_thread;
 };
 
 } // namespace WebCore
 
 #endif // AsyncAudioDecoder_h