Detect AudioInputStream muting and propagate to MediaStreamAudioSource.

content/common/media/audio_messages.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // IPC messages for the audio.
 // Multiply-included message file, hence no include guard.
 
 #include <stdint.h>
 
 #include <string>
@@ skipping 53 matching lines @@
     uint32_t /* length */,
     uint32_t /* segment count */)
 
 // Notification message sent from AudioRendererHost to renderer for state
 // update on error.
 IPC_MESSAGE_CONTROL1(AudioMsg_NotifyStreamError, int /* stream id */)
 
 // Notification message sent from browser to renderer for state update.
 IPC_MESSAGE_CONTROL1(AudioInputMsg_NotifyStreamError, int /* stream id */)
 
+// Notification message sent from browser to renderer when stream mutes or
+// unmutes.
+IPC_MESSAGE_CONTROL2(AudioInputMsg_NotifyStreamMuted,
+                     int /* stream id */,
+                     bool /* is muted? */)
+
 // Messages sent from the renderer to the browser.
 
 // Message sent to the browser to request the use of an audio output
 // device. |render_frame_id| is the routing ID for the RenderFrame producing
 // the audio data.
 IPC_MESSAGE_CONTROL5(AudioHostMsg_RequestDeviceAuthorization,
                      int /* stream_id */,
                      int /* render_frame_id */,
                      int /* session_id */,
                      std::string /* device_id */,
@@ skipping 37 matching lines @@
 // Set audio volume of the stream specified by stream_id.
 // TODO(hclam): change this to vector if we have channel numbers other than 2.
 IPC_MESSAGE_CONTROL2(AudioHostMsg_SetVolume,
                      int /* stream_id */,
                      double /* volume */)
 
 // Set audio volume of the input stream specified by stream_id.
 IPC_MESSAGE_CONTROL2(AudioInputHostMsg_SetVolume,
                      int /* stream_id */,
                      double /* volume */)