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

media/audio/audio_input_controller.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.
 
 #ifndef MEDIA_AUDIO_AUDIO_INPUT_CONTROLLER_H_
 #define MEDIA_AUDIO_AUDIO_INPUT_CONTROLLER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 86 matching lines @@
 
     // Native input stream reports an error. Exact reason differs between
     // platforms.
     STREAM_ERROR,  // = 3
   };
 
   // An event handler that receives events from the AudioInputController. The
   // following methods are all called on the audio thread.
   class MEDIA_EXPORT EventHandler {
    public:
-    virtual void OnCreated(AudioInputController* controller) = 0;
+    // The initial "muted" state of the underlying stream is sent along with the
+    // OnCreated callback, to avoid the stream being treated as unmuted until an
+    // OnMuted callback has had time to be processed.
+    virtual void OnCreated(AudioInputController* controller,
+                           bool initially_muted) = 0;
     virtual void OnError(AudioInputController* controller,
                          ErrorCode error_code) = 0;
     virtual void OnLog(AudioInputController* controller,
                        const std::string& message) = 0;
-    // Initially, an AudioInputController is considered not muted. If the
-    // underlying stream is actually muted, an OnMuted callback will follow
-    // shortly after OnCreated. It is also called whenever the muted state of
-    // the underlying stream changes.
+    // Called whenever the muted state of the underlying stream changes.
     virtual void OnMuted(AudioInputController* controller, bool is_muted) = 0;
 
    protected:
     virtual ~EventHandler() {}
   };
 
   // A synchronous writer interface used by AudioInputController for
   // synchronous writing.
   class MEDIA_EXPORT SyncWriter {
    public:
@@ skipping 280 matching lines @@
   // The weak_ptr_factory_ and all outstanding weak pointers, are invalidated
   // at the end of DoClose.
   base::WeakPtrFactory<AudioInputController> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioInputController);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_AUDIO_INPUT_CONTROLLER_H_