WebAudio createBuffer should throw error with 0 channels.

Source/modules/webaudio/AudioBuffer.h

 /*
  * Copyright (C) 2010 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
@@ skipping 26 matching lines @@
 #include "wtf/Vector.h"
 
 namespace WebCore {
 
 class AudioBus;
 class ExceptionState;
 
 class AudioBuffer : public ScriptWrappable, public RefCounted<AudioBuffer> {
 public:
     static PassRefPtr<AudioBuffer> create(unsigned numberOfChannels, size_t numberOfFrames, float sampleRate);
+    static PassRefPtr<AudioBuffer> create(unsigned numberOfChannels, size_t numberOfFrames, float sampleRate, ExceptionState&);
 
     // Returns 0 if data is not a valid audio file.
     static PassRefPtr<AudioBuffer> createFromAudioFileData(const void* data, size_t dataSize, bool mixToMono, float sampleRate);
 
     // Format
     size_t length() const { return m_length; }
     double duration() const { return length() / static_cast<double>(sampleRate()); }
     float sampleRate() const { return m_sampleRate; }
 
     // Channel data access
@@ skipping 11 matching lines @@
 
     float m_sampleRate;
     size_t m_length;
 
     Vector<RefPtr<Float32Array> > m_channels;
 };
 
 } // namespace WebCore
 
 #endif // AudioBuffer_h