Added initial set of logging for AudioOutputController.

media/audio/audio_output_controller_unittest.cc

Index: media/audio/audio_output_controller_unittest.cc
diff --git a/media/audio/audio_output_controller_unittest.cc b/media/audio/audio_output_controller_unittest.cc
index 84e3c6fade4264b707b334fbc66e156e22799d90..2919808af645614f2fe24015dfd3c1482ff68711 100644
--- a/media/audio/audio_output_controller_unittest.cc
+++ b/media/audio/audio_output_controller_unittest.cc
@@ -53,6 +53,7 @@ class MockAudioOutputControllerEventHandler
   MOCK_METHOD0(OnControllerPlaying, void());
   MOCK_METHOD0(OnControllerPaused, void());
   MOCK_METHOD0(OnControllerError, void());
+  MOCK_METHOD1(OnLog, void(const std::string&));
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MockAudioOutputControllerEventHandler);