Add groupid for media devices. Group audio devices.

media/audio/mock_audio_manager.h

Index: media/audio/mock_audio_manager.h
diff --git a/media/audio/mock_audio_manager.h b/media/audio/mock_audio_manager.h
index 6b3994c0462556b33aec1eb119e98e024923b6bc..6301ffec3a541348bc366301cb78b2c813f0541a 100644
--- a/media/audio/mock_audio_manager.h
+++ b/media/audio/mock_audio_manager.h
@@ -56,6 +56,8 @@ class MockAudioManager : public media::AudioManager {
       const std::string& device_id) override;
   std::string GetAssociatedOutputDeviceID(
       const std::string& input_device_id) override;
+  std::string GetGroupIDOutput(std::string output_id) override;
+  std::string GetGroupIDInput(std::string input_id) override;
 
   std::unique_ptr<AudioLog> CreateAudioLog(
       AudioLogFactory::AudioComponent component) override;