[WIP]Add WebPrivateHeapPtr and use it for speech platform layer.

Source/web/WebSpeechRecognitionResult.cpp

 /*
  * 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 49 matching lines @@
         alternatives[i] = WebCore::SpeechRecognitionAlternative::create(transcripts[i], confidences[i]);
 
     m_private = WebCore::SpeechRecognitionResult::create(alternatives, final);
 }
 
 void WebSpeechRecognitionResult::reset()
 {
     m_private.reset();
 }
 
-WebSpeechRecognitionResult::operator PassRefPtr<WebCore::SpeechRecognitionResult>() const
+WebSpeechRecognitionResult::operator PassRefPtrWillBeRawPtr<WebCore::SpeechRecognitionResult>() const

[haraken, 2014/02/17 09:04:57]

I'm afraid that this implicit conversion will lead to unexpected error. Shall we
remove this? (We've removed this kind of implicit conversions from the
experimental branch.)

 {
     return m_private.get();
 }
 
 } // namespace blink