HRTF panner should handle the case of no loaded HRTF database

third_party/WebKit/Source/platform/audio/EqualPowerPanner.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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 17 matching lines @@
 #include "platform/audio/Panner.h"
 
 namespace blink {
 
 // Common type of stereo panner as found in normal audio mixing equipment.
 
 class PLATFORM_EXPORT EqualPowerPanner final : public Panner {
 public:
     EqualPowerPanner(float sampleRate);
 
-    void pan(double azimuth, double elevation, const AudioBus* inputBus, AudioBus* outputBuf, size_t framesToProcess) override;
-    void panWithSampleAccurateValues(double* azimuth, double* elevation, const AudioBus* inputBus, AudioBus* outputBus, size_t framesToProcess) override;
+    void pan(double azimuth, double elevation, const AudioBus* inputBus, AudioBus* outputBuf, size_t framesToProcess, AudioBus::ChannelInterpretation) override;
+    void panWithSampleAccurateValues(double* azimuth, double* elevation, const AudioBus* inputBus, AudioBus* outputBus, size_t framesToProcess, AudioBus::ChannelInterpretation) override;
 
     void reset() override { }
 
     double tailTime() const override { return 0; }
     double latencyTime() const override { return 0; }
 
 private:
     void calculateDesiredGain(double& desiredGainL, double& desiredGainR, double azimuth, int numberOfChannels);
 };
 
 } // namespace blink
 
 #endif // EqualPowerPanner_h