Let Contraints Controll Mute/Unmute Audio Local Playback For Desktop Sharing

third_party/WebKit/public/platform/WebMediaConstraints.h

 /*
  * 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 238 matching lines @@
     LongConstraint sampleRate;
     LongConstraint sampleSize;
     BooleanConstraint echoCancellation;
     DoubleConstraint latency;
     LongConstraint channelCount;
     StringConstraint deviceId;
     StringConstraint groupId;
     // Constraints not exposed in Blink at the moment, only through
     // the legacy name interface.
     StringConstraint mediaStreamSource; // tab, screen, desktop, system
+    BooleanConstraint muteSourceAudio;
     BooleanConstraint renderToAssociatedSink;
     BooleanConstraint hotwordEnabled;
     BooleanConstraint googEchoCancellation;
     BooleanConstraint googExperimentalEchoCancellation;
     BooleanConstraint googAutoGainControl;
     BooleanConstraint googExperimentalAutoGainControl;
     BooleanConstraint googNoiseSuppression;
     BooleanConstraint googHighpassFilter;
     BooleanConstraint googTypingNoiseDetection;
     BooleanConstraint googExperimentalNoiseSuppression;
@@ skipping 63 matching lines @@
 
     BLINK_PLATFORM_EXPORT const WebString toString() const;
 
 private:
     WebPrivatePtr<WebMediaConstraintsPrivate> m_private;
 };
 
 } // namespace blink
 
 #endif // WebMediaConstraints_h