Added UMA metrics for MediaSourcePlayer and MediaCodecPlayer

media/base/android/media_codec_audio_decoder.cc

Index: media/base/android/media_codec_audio_decoder.cc
diff --git a/media/base/android/media_codec_audio_decoder.cc b/media/base/android/media_codec_audio_decoder.cc
index 88bdeb5de2ea122a8aeedb6e12634a2b4f18a0a3..19de52ca5192e5903f513bea02efde797ffc4522 100644
--- a/media/base/android/media_codec_audio_decoder.cc
+++ b/media/base/android/media_codec_audio_decoder.cc
@@ -7,6 +7,7 @@
 #include "base/bind.h"
 #include "base/logging.h"
 #include "media/base/android/media_codec_bridge.h"
+#include "media/base/android/media_statistics.h"
 #include "media/base/audio_timestamp_helper.h"
 #include "media/base/demuxer_stream.h"
 
@@ -27,7 +28,8 @@ MediaCodecAudioDecoder::MediaCodecAudioDecoder(
     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)
     : MediaCodecDecoder(media_task_runner,
                         request_data_cb,
                         starvation_cb,
@@ -35,7 +37,8 @@ MediaCodecAudioDecoder::MediaCodecAudioDecoder(
                         stop_done_cb,
                         key_required_cb,
                         error_cb,
-                        "AudioDecoder"),
+                        "AudioDecoder",
+                        frame_statistics),
       volume_(-1.0),
       bytes_per_frame_(0),
       output_sampling_rate_(0),
@@ -205,6 +208,11 @@ void MediaCodecAudioDecoder::Render(int buffer_index,
     int64 head_position =
         audio_codec->PlayOutputBuffer(buffer_index, size, offset, postpone);
 
+    base::TimeTicks current_time = base::TimeTicks::Now();
+
+    if (frame_statistics_)
+      frame_statistics_->AddFrame();

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

When can frame_statistics_ be null? Is it only in unit tests? If so, can we fix
the test and always make sure frame_statistics_ is non-null?

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

Done.

+
     // Reset the base timestamp if we have not started playing.
     // SetBaseTimestamp() must be called before AddFrames() since it resets the
     // internal frame count.
@@ -238,6 +246,13 @@ void MediaCodecAudioDecoder::Render(int buffer_index,
       DVLOG(2) << class_name() << "::" << __FUNCTION__ << " pts:" << pts
                << " will play: [" << now_playing << "," << last_buffered << "]";
 
+      // Statistics
+      if (frame_statistics_ && !next_frame_time_limit_.is_null() &&
+          next_frame_time_limit_ < current_time)
+        frame_statistics_->AddLateFrame(current_time - next_frame_time_limit_);
+
+      next_frame_time_limit_ = current_time + (last_buffered - now_playing);
+
       media_task_runner_->PostTask(
           FROM_HERE, base::Bind(update_current_time_cb_, now_playing,
                                 last_buffered, false));
@@ -246,7 +261,10 @@ void MediaCodecAudioDecoder::Render(int buffer_index,
 
   media_codec_bridge_->ReleaseOutputBuffer(buffer_index, false);
 
-  CheckLastFrame(eos_encountered, false);  // no delayed tasks
+  if (CheckLastFrame(eos_encountered, false)) {  // no delayed tasks
+    // This is the last frame
+    next_frame_time_limit_ = base::TimeTicks();
+  }
 }
 
 void MediaCodecAudioDecoder::SetVolumeInternal() {