Added UMA metrics for MediaSourcePlayer and MediaCodecPlayer

media/base/android/media_codec_player.cc

Index: media/base/android/media_codec_player.cc
diff --git a/media/base/android/media_codec_player.cc b/media/base/android/media_codec_player.cc
index 161d59e5ddd113ba715a3c5a88caa03d849819a2..10f88c041aacdff22341cabf919bd892e85b5b64 100644
--- a/media/base/android/media_codec_player.cc
+++ b/media/base/android/media_codec_player.cc
@@ -99,6 +99,8 @@ MediaCodecPlayer::~MediaCodecPlayer()
   if (audio_decoder_)
     audio_decoder_->ReleaseDecoderResources();
 
+  media_stat_->StopAndReport(GetInterpolatedTime());
+
   if (drm_bridge_) {
     DCHECK(cdm_registration_id_);
     drm_bridge_->UnregisterPlayer(cdm_registration_id_);
@@ -807,6 +809,8 @@ void MediaCodecPlayer::OnStopDone(DemuxerStream::Type type) {
       return;
   }
 
+  media_stat_->StopAndReport(GetInterpolatedTime());
+
   // DetachListener to UI thread
   ui_task_runner_->PostTask(FROM_HERE, detach_listener_cb_);
 
@@ -851,6 +855,8 @@ void MediaCodecPlayer::OnStarvation(DemuxerStream::Type type) {
   SetState(kStateStopping);
   RequestToStopDecoders();
   SetPendingStart(true);
+
+  media_stat_->AddStarvation();
 }
 
 void MediaCodecPlayer::OnTimeIntervalUpdate(DemuxerStream::Type type,
@@ -1247,6 +1253,10 @@ MediaCodecPlayer::StartStatus MediaCodecPlayer::StartDecoders() {
 
   DVLOG(1) << __FUNCTION__ << " current_time:" << current_time;
 
+  // This methos needs to be called when decoder threads are not processing

[xhwang, 2015/09/30 21:02:57]

s/methos/method

Also, I don't quite understand this comment. Could you please elaborate?

[Tima Vaisburd, 2015/10/01 20:05:15]

Changed to:
  At this point decoder threads are either not running at all or their
  message pumps are in the idel state after the preroll is done.

+  // frames.
+  media_stat_->Start(current_time);
+
   if (!AudioFinished()) {
     if (!audio_decoder_->Start(current_time))
       return kStartFailed;
@@ -1269,6 +1279,8 @@ void MediaCodecPlayer::StopDecoders() {
 
   video_decoder_->SyncStop();
   audio_decoder_->SyncStop();
+
+  media_stat_->StopAndReport(GetInterpolatedTime());
 }
 
 void MediaCodecPlayer::RequestToStopDecoders() {
@@ -1326,6 +1338,8 @@ void MediaCodecPlayer::ReleaseDecoderResources() {
   // At this point decoder threads should not be running
   if (interpolator_.interpolating())
     interpolator_.StopInterpolating();
+
+  media_stat_->StopAndReport(GetInterpolatedTime());
 }
 
 void MediaCodecPlayer::CreateDecoders() {
@@ -1334,6 +1348,8 @@ void MediaCodecPlayer::CreateDecoders() {
 
   internal_error_cb_ = base::Bind(&MediaCodecPlayer::OnError, media_weak_this_);
 
+  media_stat_.reset(new MediaStatistics());
+
   audio_decoder_.reset(new MediaCodecAudioDecoder(
       GetMediaTaskRunner(), base::Bind(&MediaCodecPlayer::RequestDemuxerData,
                                        media_weak_this_, DemuxerStream::AUDIO),
@@ -1347,7 +1363,8 @@ void MediaCodecPlayer::CreateDecoders() {
                  DemuxerStream::AUDIO),
       internal_error_cb_,
       base::Bind(&MediaCodecPlayer::OnTimeIntervalUpdate, media_weak_this_,
-                 DemuxerStream::AUDIO)));
+                 DemuxerStream::AUDIO),
+      &media_stat_->audio_frames()));
 
   video_decoder_.reset(new MediaCodecVideoDecoder(
       GetMediaTaskRunner(), base::Bind(&MediaCodecPlayer::RequestDemuxerData,
@@ -1364,7 +1381,8 @@ void MediaCodecPlayer::CreateDecoders() {
       base::Bind(&MediaCodecPlayer::OnTimeIntervalUpdate, media_weak_this_,
                  DemuxerStream::VIDEO),
       base::Bind(&MediaCodecPlayer::OnVideoResolutionChanged, media_weak_this_),
-      base::Bind(&MediaCodecPlayer::OnVideoCodecCreated, media_weak_this_)));
+      base::Bind(&MediaCodecPlayer::OnVideoCodecCreated, media_weak_this_),
+      &media_stat_->video_frames()));
 }
 
 bool MediaCodecPlayer::AudioFinished() const {