Defer changes to the channel count mode to the pre or post-render phase

Source/modules/webaudio/AudioNode.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 36 matching lines @@
 
 AudioNode::AudioNode(AudioContext* context, float sampleRate)
     : m_isInitialized(false)
     , m_nodeType(NodeTypeUnknown)
     , m_context(context)
     , m_sampleRate(sampleRate)
     , m_lastProcessingTime(-1)
     , m_lastNonSilentTime(-1)
     , m_connectionRefCount(0)
     , m_isDisabled(false)
+    , m_newChannelCountMode(Max)
     , m_channelCount(2)
     , m_channelCountMode(Max)
     , m_channelInterpretation(AudioBus::Speakers)
 {
     ScriptWrappable::init(this);
     m_context->registerLiveNode(*this);
 #if DEBUG_AUDIONODE_REFERENCES
     if (!s_isNodeCountInitialized) {
         s_isNodeCountInitialized = true;
         atexit(AudioNode::printNodeCounts);
@@ skipping 19 matching lines @@
 void AudioNode::uninitialize()
 {
     m_isInitialized = false;
 }
 
 void AudioNode::dispose()
 {
     ASSERT(isMainThread());
     ASSERT(context()->isGraphOwner());
 
+    context()->removeChangedChannelCountMode(this);
     context()->removeAutomaticPullNode(this);
     context()->disposeOutputs(*this);
     for (unsigned i = 0; i < m_outputs.size(); ++i)
         output(i)->disconnectAll();
 }
 
 String AudioNode::nodeTypeName() const
 {
     switch (m_nodeType) {
     case NodeTypeDestination:
@@ skipping 196 matching lines @@
 }
 
 void AudioNode::setChannelCountMode(const String& mode, ExceptionState& exceptionState)
 {
     ASSERT(isMainThread());
     AudioContext::AutoLocker locker(context());
 
     ChannelCountMode oldMode = m_channelCountMode;
 
     if (mode == "max") {
-        m_channelCountMode = Max;
+        m_newChannelCountMode = Max;
     } else if (mode == "clamped-max") {
-        m_channelCountMode = ClampedMax;
+        m_newChannelCountMode = ClampedMax;
     } else if (mode == "explicit") {
-        m_channelCountMode = Explicit;
+        m_newChannelCountMode = Explicit;
     } else {
         ASSERT_NOT_REACHED();
     }
 
-    if (m_channelCountMode != oldMode)
-        updateChannelsForInputs();
+    if (m_newChannelCountMode != oldMode)
+        context()->addChangedChannelCountMode(this);
 }
 
 String AudioNode::channelInterpretation()
 {
     switch (m_channelInterpretation) {
     case AudioBus::Speakers:
         return "speakers";
     case AudioBus::Discrete:
         return "discrete";
     }
@@ skipping 211 matching lines @@
 #endif // DEBUG_AUDIONODE_REFERENCES
 
 void AudioNode::trace(Visitor* visitor)
 {
     visitor->trace(m_context);
     visitor->trace(m_inputs);
     visitor->trace(m_outputs);
     EventTargetWithInlineData::trace(visitor);
 }
 
+void AudioNode::updateChannelCountMode()
+{
+    m_channelCountMode = m_newChannelCountMode;
+    updateChannelsForInputs();
+}
+
 } // namespace blink
 
 #endif // ENABLE(WEB_AUDIO)