Link things together and enable the device selection for linux and mac.

content/renderer/media/webrtc_audio_device_impl.h

 // Copyright (c) 2011 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_WEBRTC_AUDIO_DEVICE_IMPL_H_
 #define CONTENT_RENDERER_MEDIA_WEBRTC_AUDIO_DEVICE_IMPL_H_
 #pragma once
 
 #include <vector>
 
@@ skipping 102 matching lines @@
   virtual void Render(const std::vector<float*>& audio_data,
                       size_t number_of_frames,
                       size_t audio_delay_milliseconds) OVERRIDE;
 
   // AudioInputDevice::CaptureCallback implementation.
   virtual void Capture(const std::vector<float*>& audio_data,
                        size_t number_of_frames,
                        size_t audio_delay_milliseconds) OVERRIDE;
 
   // AudioInputDevice::CaptureEventHandler implementation.
-  virtual void OnDeviceStarted(int device_index);
+  virtual void OnDeviceStarted(const std::string& device_id);
   virtual void OnDeviceStopped();
 
   // webrtc::Module implementation.
   virtual int32_t Version(char* version,
                           uint32_t& remaining_buffer_in_bytes,
                           uint32_t& position) const OVERRIDE;
   virtual int32_t ChangeUniqueId(const int32_t id) OVERRIDE;
   virtual int32_t TimeUntilNextProcess() OVERRIDE;
   virtual int32_t Process() OVERRIDE;
 
@@ skipping 183 matching lines @@
   int bytes_per_sample_;
 
   bool initialized_;
   bool playing_;
   bool recording_;
 
   DISALLOW_COPY_AND_ASSIGN(WebRtcAudioDeviceImpl);
 };
 
 #endif  // CONTENT_RENDERER_MEDIA_WEBRTC_AUDIO_DEVICE_IMPL_H_