Added UMA metrics for MediaSourcePlayer and MediaCodecPlayer

media/base/android/media_codec_audio_decoder.h

Index: media/base/android/media_codec_audio_decoder.h
diff --git a/media/base/android/media_codec_audio_decoder.h b/media/base/android/media_codec_audio_decoder.h
index ab6765aca75136bf4c5825adbe0a23cfceeeba6f..3e3ba8376d51021ce2ac28aedccb6a103336c9d1 100644
--- a/media/base/android/media_codec_audio_decoder.h
+++ b/media/base/android/media_codec_audio_decoder.h
@@ -25,7 +25,8 @@ class MediaCodecAudioDecoder : public MediaCodecDecoder {
       const base::Closure& stop_done_cb,
       const base::Closure& key_required_cb,
       const base::Closure& error_cb,
-      const SetTimeCallback& update_current_time_cb);
+      const SetTimeCallback& update_current_time_cb,
+      FrameStatistics* frame_statistics);
   ~MediaCodecAudioDecoder() override;
 
   const char* class_name() const override;
@@ -87,6 +88,9 @@ class MediaCodecAudioDecoder : public MediaCodecDecoder {
   // Reports current playback time to the callee.
   SetTimeCallback update_current_time_cb_;
 
+  // The time limit for the next frame to avoid underrun.
+  base::TimeTicks next_frame_time_limit_;
+
   DISALLOW_COPY_AND_ASSIGN(MediaCodecAudioDecoder);
 };