Add safety when the .src attribute of an <audio> or <video> element is changed and it's used with t…

Source/WebKit/chromium/src/WebMediaPlayerClientImpl.h

 /*
  * Copyright (C) 2009 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
@@ skipping 213 matching lines @@
         // Wraps the given WebAudioSourceProvider.
         void wrap(WebAudioSourceProvider*);
 
         // WebCore::AudioSourceProvider
         virtual void setClient(WebCore::AudioSourceProviderClient*);
         virtual void provideInput(WebCore::AudioBus*, size_t framesToProcess);
 
     private:
         WebAudioSourceProvider* m_webAudioSourceProvider;
         OwnPtr<AudioClientImpl> m_client;
+        Mutex provideInputLock;
     };
 
     AudioSourceProviderImpl m_audioSourceProvider;
 #endif
 
     RefPtr<WebCore::MediaSource> m_mediaSource;
 };
 
 } // namespace WebKit
 
 #endif