Oilpan: prefer eager finalization over prefinalizers.

Source/platform/speech/PlatformSpeechSynthesizer.cpp

 /*
  * Copyright (C) 2013 Apple Computer, 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 30 matching lines @@
     PlatformSpeechSynthesizer* synthesizer = new PlatformSpeechSynthesizer(client);
     synthesizer->initializeVoiceList();
     return synthesizer;
 }
 
 PlatformSpeechSynthesizer::PlatformSpeechSynthesizer(PlatformSpeechSynthesizerClient* client)
     : m_speechSynthesizerClient(client)
 {
     m_webSpeechSynthesizerClient = new WebSpeechSynthesizerClientImpl(this, client);
     m_webSpeechSynthesizer = adoptPtr(Platform::current()->createSpeechSynthesizer(m_webSpeechSynthesizerClient));
-    ThreadState::current()->registerPreFinalizer(*this);
 }
 
 PlatformSpeechSynthesizer::~PlatformSpeechSynthesizer()
 {
 }
 
-// Since the m_webSpeechSynthesizer (i.e., TtsDispatcher in the chrome side)
-// holds a raw pointer back to the m_webSpeechSynthesizerClient, we need to
-// make sure that the raw pointer is cleared before the sweeping starts.
-// Otherwise, m_webSpeechSynthesizerClient might end up being lazily swept
-// before this PlatformSpeechSynthesizer object is, leaving
-// m_sweepSpeechSynthesizer with a dangling pointer to a freed object.
-void PlatformSpeechSynthesizer::dispose()
-{
-    m_webSpeechSynthesizer.clear();
-}
-
 void PlatformSpeechSynthesizer::speak(PlatformSpeechSynthesisUtterance* utterance)
 {
     if (m_webSpeechSynthesizer && m_webSpeechSynthesizerClient)
         m_webSpeechSynthesizer->speak(WebSpeechSynthesisUtterance(utterance));
 }
 
 void PlatformSpeechSynthesizer::pause()
 {
     if (m_webSpeechSynthesizer.get())
         m_webSpeechSynthesizer->pause();
@@ skipping 23 matching lines @@
 }
 
 DEFINE_TRACE(PlatformSpeechSynthesizer)
 {
     visitor->trace(m_speechSynthesizerClient);
     visitor->trace(m_voiceList);
     visitor->trace(m_webSpeechSynthesizerClient);
 }
 
 } // namespace blink