Support for AudioContextOptions latencyHint.

third_party/WebKit/Source/modules/webaudio/AudioDestinationNode.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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 15 matching lines @@
 #include "modules/webaudio/AudioDestinationNode.h"
 #include "modules/webaudio/AudioNodeInput.h"
 #include "modules/webaudio/AudioNodeOutput.h"
 #include "modules/webaudio/BaseAudioContext.h"
 #include "platform/audio/AudioUtilities.h"
 #include "platform/audio/DenormalDisabler.h"
 #include "wtf/Atomics.h"
 
 namespace blink {
 
-AudioDestinationHandler::AudioDestinationHandler(AudioNode& node,
-                                                 float sampleRate)
-    : AudioHandler(NodeTypeDestination, node, sampleRate),
-      m_currentSampleFrame(0) {
+AudioDestinationHandler::AudioDestinationHandler(AudioNode& node)
+    : AudioHandler(NodeTypeDestination, node, 0), m_currentSampleFrame(0) {

[hongchan, 2016/12/02 17:40:12]

So the initial sample rate is zero? Not sure why this change is necessary here.

[Andrew MacPherson, 2016/12/05 14:12:53]

I mentioned in an earlier comment to rtoy@ that the sample rate passed into the
AudioHandler() constructor is no longer used anywhere and should be removed but
I wasn't sure if I should include that as part of this CL since it touches a
number of files in the webaudio code. I'm happy to take care of it right now
though if that's best!

   addInput();
 }
 
 AudioDestinationHandler::~AudioDestinationHandler() {
   DCHECK(!isInitialized());
 }
 
 void AudioDestinationHandler::render(AudioBus* sourceBus,
                                      AudioBus* destinationBus,
                                      size_t numberOfFrames) {
@@ skipping 66 matching lines @@
 
 AudioDestinationHandler& AudioDestinationNode::audioDestinationHandler() const {
   return static_cast<AudioDestinationHandler&>(handler());
 }
 
 unsigned long AudioDestinationNode::maxChannelCount() const {
   return audioDestinationHandler().maxChannelCount();
 }
 
 }  // namespace blink