Add support for the audio-output-device switching IPC mechanism to the renderer lower layers (media…

media/audio/audio_output_device.h

Index: media/audio/audio_output_device.h
diff --git a/media/audio/audio_output_device.h b/media/audio/audio_output_device.h
index 6255c71fdba8e99155622d78b7abc825a94cb256..dc28352958eebfd267fca1f23164ddc08da759b3 100644
--- a/media/audio/audio_output_device.h
+++ b/media/audio/audio_output_device.h
@@ -58,6 +58,8 @@
 #ifndef MEDIA_AUDIO_AUDIO_OUTPUT_DEVICE_H_
 #define MEDIA_AUDIO_AUDIO_OUTPUT_DEVICE_H_
 
+#include <string>
+
 #include "base/basictypes.h"
 #include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
@@ -95,6 +97,9 @@ class MEDIA_EXPORT AudioOutputDevice
   void Play() override;
   void Pause() override;
   bool SetVolume(double volume) override;
+  void SwitchOutputDevice(const std::string& device_id,
+                          const GURL& security_origin,
+                          const SwitchOutputDeviceCB& callback) override;
 
   // Methods called on IO thread ----------------------------------------------
   // AudioOutputIPCDelegate methods.
@@ -102,6 +107,8 @@ class MEDIA_EXPORT AudioOutputDevice
   void OnStreamCreated(base::SharedMemoryHandle handle,
                        base::SyncSocket::Handle socket_handle,
                        int length) override;
+  void OnOutputDeviceSwitched(int request_id,
+                              SwitchOutputDeviceResult result) override;
   void OnIPCClosed() override;
 
  protected:
@@ -129,11 +136,16 @@ class MEDIA_EXPORT AudioOutputDevice
   void PauseOnIOThread();
   void ShutDownOnIOThread();
   void SetVolumeOnIOThread(double volume);
+  void SwitchOutputDeviceOnIOThread(const std::string& device_id,
+                                    const GURL& security_origin,
+                                    const SwitchOutputDeviceCB& callback);
 
   // base::MessageLoop::DestructionObserver implementation for the IO loop.
   // If the IO loop dies before we do, we shut down the audio thread from here.
   void WillDestroyCurrentMessageLoop() override;
 
+  void SetCurrentSwitchRequest(const SwitchOutputDeviceCB& callback);
+
   AudioParameters audio_parameters_;
 
   RenderCallback* callback_;
@@ -171,6 +183,9 @@ class MEDIA_EXPORT AudioOutputDevice
   // the callback via Start(). See http://crbug.com/151051 for details.
   bool stopping_hack_;
 
+  int current_switch_request_id_;
+  SwitchOutputDeviceCB current_switch_callback_;
+
   DISALLOW_COPY_AND_ASSIGN(AudioOutputDevice);
 };