Avoid unsafe heap access from audio thread.

third_party/WebKit/Source/modules/webaudio/OfflineAudioContext.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:
  * 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 370 matching lines @@
   HandleStoppableSourceNodes();
 
   return ShouldSuspend();
 }
 
 void OfflineAudioContext::HandlePostOfflineRenderTasks() {
   DCHECK(IsAudioThread());
 
   // OfflineGraphAutoLocker here locks the audio graph for the same reason
   // above in |handlePreOfflineRenderTasks|.
-  bool did_remove = false;
   {
     OfflineGraphAutoLocker locker(this);
 
     GetDeferredTaskHandler().BreakConnections();
-    did_remove = ReleaseFinishedSourceNodes();
     GetDeferredTaskHandler().HandleDeferredTasks();
     GetDeferredTaskHandler().RequestToDeleteHandlersOnMainThread();
   }
-
-  RemoveFinishedSourceNodes(did_remove);
 }
 
 OfflineAudioDestinationHandler& OfflineAudioContext::DestinationHandler() {
   return static_cast<OfflineAudioDestinationHandler&>(
       destination()->GetAudioDestinationHandler());
 }
 
 void OfflineAudioContext::ResolveSuspendOnMainThread(size_t frame) {
   DCHECK(IsMainThread());
 
@@ skipping 41 matching lines @@
 
   // Note that the GraphLock is required before this check. Since this needs
   // to run on the audio thread, OfflineGraphAutoLocker must be used.
   if (scheduled_suspends_.Contains(CurrentSampleFrame()))
     return true;
 
   return false;
 }
 
 }  // namespace blink