Supporting a playbackTime attribute on AudioprocessingEvent.

Source/modules/webaudio/AudioProcessingEvent.h

Index: Source/modules/webaudio/AudioProcessingEvent.h
diff --git a/Source/modules/webaudio/AudioProcessingEvent.h b/Source/modules/webaudio/AudioProcessingEvent.h
index 23f61f0906be7258a35dc8e58884f0e29b5943e7..4458e6a357178229166ad6068fb98ba0748a8f8b 100644
--- a/Source/modules/webaudio/AudioProcessingEvent.h
+++ b/Source/modules/webaudio/AudioProcessingEvent.h
@@ -37,12 +37,13 @@ class AudioBuffer;
 class AudioProcessingEvent FINAL : public Event {
 public:
     static PassRefPtr<AudioProcessingEvent> create();
-    static PassRefPtr<AudioProcessingEvent> create(PassRefPtr<AudioBuffer> inputBuffer, PassRefPtr<AudioBuffer> outputBuffer);
+    static PassRefPtr<AudioProcessingEvent> create(PassRefPtr<AudioBuffer> inputBuffer, PassRefPtr<AudioBuffer> outputBuffer, double playbackTime);
 
     virtual ~AudioProcessingEvent();
 
     AudioBuffer* inputBuffer() { return m_inputBuffer.get(); }
     AudioBuffer* outputBuffer() { return m_outputBuffer.get(); }
+    double playbackTime() const { return m_playbackTime; }
 
     virtual const AtomicString& interfaceName() const OVERRIDE;
 
@@ -50,10 +51,11 @@ public:
 
 private:
     AudioProcessingEvent();
-    AudioProcessingEvent(PassRefPtr<AudioBuffer> inputBuffer, PassRefPtr<AudioBuffer> outputBuffer);
+    AudioProcessingEvent(PassRefPtr<AudioBuffer> inputBuffer, PassRefPtr<AudioBuffer> outputBuffer, double playbackTime);
 
     RefPtr<AudioBuffer> m_inputBuffer;
     RefPtr<AudioBuffer> m_outputBuffer;
+    double m_playbackTime;
 };
 
 } // namespace WebCore