Make ConvolverNode conform to spec

third_party/WebKit/Source/platform/audio/Reverb.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 56 matching lines @@
   size_t latencyFrames() const;
 
  private:
   void initialize(AudioBus* impulseResponseBuffer,
                   size_t renderSliceSize,
                   size_t maxFFTSize,
                   size_t numberOfChannels,
                   bool useBackgroundThreads);
 
   size_t m_impulseResponseLength;
+  // The actual number of channels in the response.  This can be less
+  // than the number of ReverbConvolver's.
+  unsigned m_numberOfChannels;
 
   Vector<std::unique_ptr<ReverbConvolver>> m_convolvers;
 
   // For "True" stereo processing
   RefPtr<AudioBus> m_tempBuffer;
 };
 
 }  // namespace blink
 
 #endif  // Reverb_h