Added initial muted state to stream creation callback, to avoid races.

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 36 matching lines @@
 // it uses to communicate with the browser process about the state of the
 // buffered audio data.
 IPC_MESSAGE_CONTROL4(
     AudioMsg_NotifyStreamCreated,
     int /* stream id */,
     base::SharedMemoryHandle /* handle */,
     base::SyncSocket::TransitDescriptor /* socket descriptor */,
     uint32_t /* length */)
 
 // Tell the renderer process that an audio input stream has been created.
-// The renderer process would be given a SyncSocket that it should read
-// from from then on. It is also given number of segments in shared memory.
-IPC_MESSAGE_CONTROL5(
-    AudioInputMsg_NotifyStreamCreated,
-    int /* stream id */,
-    base::SharedMemoryHandle /* handle */,
-    base::SyncSocket::TransitDescriptor /* socket descriptor */,
-    uint32_t /* length */,
-    uint32_t /* segment count */)
+// The renderer process would be given a SyncSocket that it should read from
+// from then on. It is also given number of segments in shared memory and
+// whether the stream initially is muted.
+IPC_MESSAGE_CONTROL(AudioInputMsg_NotifyStreamCreated,
+                    int /* stream id */,
+                    base::SharedMemoryHandle /* handle */,
+                    base::SyncSocket::TransitDescriptor /* socket descriptor */,
+                    uint32_t /* length */,
+                    uint32_t /* segment count */,
+                    bool /* initially muted */)
 
 // 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.
@@ skipping 51 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 */)