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

media/audio/audio_input_controller.h

Index: media/audio/audio_input_controller.h
diff --git a/media/audio/audio_input_controller.h b/media/audio/audio_input_controller.h
index fdc29cf6d8f60711a8a5ce0492de466f2f59e8e4..9b783ce9506575e2d34d7d44898a0a59ce6b65f7 100644
--- a/media/audio/audio_input_controller.h
+++ b/media/audio/audio_input_controller.h
@@ -93,6 +93,7 @@ class MEDIA_EXPORT AudioInputController
   static scoped_refptr<AudioInputController> CreateLowLatency(
       EventHandler* event_handler,
       const AudioParameters& params,
+      const std::string& device_uid,
       // External synchronous reader for audio controller.
       SyncWriter* sync_writer);
 
@@ -135,7 +136,7 @@ class MEDIA_EXPORT AudioInputController
   AudioInputController(EventHandler* handler, SyncWriter* sync_writer);
 
   // The following methods are executed on the audio controller thread.
-  void DoCreate(const AudioParameters& params);
+  void DoCreate(const AudioParameters& params, const std::string& device_uid);
   void DoRecord();
   void DoClose();
   void DoReportError(int code);