Allow Panner.refDistance to be 0

third_party/WebKit/Source/platform/audio/Distance.cpp

 /*
  * 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 49 matching lines @@
 
 double DistanceEffect::LinearGain(double distance) {
   // We want a gain that decreases linearly from m_refDistance to
   // m_maxDistance. The gain is 1 at m_refDistance.
   return (1.0 - clampTo(rolloff_factor_, 0.0, 1.0) *
                     (distance - ref_distance_) /
                     (max_distance_ - ref_distance_));
 }
 
 double DistanceEffect::InverseGain(double distance) {
+  if (ref_distance_ == 0)
+    return 0;
+
   return ref_distance_ / (ref_distance_ + clampTo(rolloff_factor_, 0.0) *
                                               (distance - ref_distance_));
 }
 
 double DistanceEffect::ExponentialGain(double distance) {
+  if (ref_distance_ == 0)
+    return 0;
+
   return pow(distance / ref_distance_, -clampTo(rolloff_factor_, 0.0));
 }
 
 }  // namespace blink