Support for AudioContextOptions latencyHint.

third_party/WebKit/Source/modules/webaudio/AudioScheduledSourceNode.cpp

 /*
  * Copyright (C) 2012, 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 43 matching lines @@
     double& startFrameOffset) {
   DCHECK(outputBus);
   if (!outputBus)
     return;
 
   DCHECK_EQ(quantumFrameSize,
             static_cast<size_t>(AudioUtilities::kRenderQuantumFrames));
   if (quantumFrameSize != AudioUtilities::kRenderQuantumFrames)
     return;
 
-  double sampleRate = this->sampleRate();
+  double sampleRate = context()->sampleRate();
 
   // quantumStartFrame     : Start frame of the current time quantum.
   // quantumEndFrame       : End frame of the current time quantum.
   // startFrame            : Start frame for this source.
   // endFrame              : End frame for this source.
   size_t quantumStartFrame = context()->currentSampleFrame();
   size_t quantumEndFrame = quantumStartFrame + quantumFrameSize;
   size_t startFrame =
       AudioUtilities::timeToSampleFrame(m_startTime, sampleRate);
   size_t endFrame =
@@ skipping 205 matching lines @@
   // playback state if the context is closed.
   if (context()->isContextClosed())
     return false;
 
   // If a node is scheduled or playing, do not collect the node prematurely
   // even its reference is out of scope. Then fire onended event if assigned.
   return audioScheduledSourceHandler().isPlayingOrScheduled();
 }
 
 }  // namespace blink