Getting rid of AudioHardwareConfig and its synchronous IPC.

content/renderer/media/audio_device_factory.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 CONTENT_RENDERER_MEDIA_AUDIO_DEVICE_FACTORY_H_
 #define CONTENT_RENDERER_MEDIA_AUDIO_DEVICE_FACTORY_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 67 matching lines @@
   // Basing on |source_type| and build configuration, audio played out through
   // the sink goes to AOD directly or can be mixed with other audio before that.
   static scoped_refptr<media::SwitchableAudioRendererSink>
   NewSwitchableAudioRendererSink(SourceType source_type,
                                  int render_frame_id,
                                  int session_id,
                                  const std::string& device_id,
                                  const url::Origin& security_origin);
 
   // A helper to get device info in the absence of AudioOutputDevice.
+  // Must be called on renderer thread only.
   static media::OutputDeviceInfo GetOutputDeviceInfo(
       int render_frame_id,
       int session_id,
       const std::string& device_id,
       const url::Origin& security_origin);
 
   // Creates an AudioCapturerSource using the currently registered factory.
   // |render_frame_id| refers to the RenderFrame containing the entity
   // consuming the audio.
   static scoped_refptr<media::AudioCapturerSource> NewAudioCapturerSource(
@@ skipping 43 matching lines @@
       int session_id,
       const std::string& device_id,
       const url::Origin& security_origin);
 
   DISALLOW_COPY_AND_ASSIGN(AudioDeviceFactory);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_AUDIO_DEVICE_FACTORY_H_