Add UMA metrics for VideoCodec.MP4 and VideoCodec.WebM

media/filters/ffmpeg_demuxer.cc

Index: media/filters/ffmpeg_demuxer.cc
diff --git a/media/filters/ffmpeg_demuxer.cc b/media/filters/ffmpeg_demuxer.cc
index 081bcbf1a452be23ee45adb6a080e11bd5b55c77..c3d6d9a3b96984fe564ed630f937bd8357368c4c 100644
--- a/media/filters/ffmpeg_demuxer.cc
+++ b/media/filters/ffmpeg_demuxer.cc
@@ -160,7 +160,8 @@ static void RecordAudioCodecStats(const AudioDecoderConfig& audio_config) {
 }
 
 // Record video decoder config UMA stats corresponding to a src= playback.
-static void RecordVideoCodecStats(const VideoDecoderConfig& video_config,
+static void RecordVideoCodecStats(const std::string& format_names,

[xhwang, 2017/04/27 16:32:50]

Can you add a comment about what "format_names" should look like?

[kqyang, 2017/04/27 18:12:53]

Done.

+                                  const VideoDecoderConfig& video_config,
                                   AVColorRange color_range,
                                   MediaLog* media_log) {
   media_log->RecordRapporWithSecurityOrigin("Media.OriginUrl.SRC.VideoCodec." +
@@ -168,6 +169,13 @@ static void RecordVideoCodecStats(const VideoDecoderConfig& video_config,
 
   UMA_HISTOGRAM_ENUMERATION("Media.VideoCodec", video_config.codec(),
                             kVideoCodecMax + 1);
+  if (format_names.find("mp4") != std::string::npos) {

[xhwang, 2017/04/27 16:32:50]

What will happen if we have a file named mp4.webm?

[kqyang, 2017/04/27 18:12:53]

|format_names| only contains format names :) Hopefully it will be clearer with
the comments above.

Also changed the code to pass in "const char*" to avoid an extra copying in
string construction.

+    UMA_HISTOGRAM_ENUMERATION("Media.VideoCodec.MP4", video_config.codec(),
+                              kVideoCodecMax + 1);
+  } else if (format_names.find("webm") != std::string::npos) {
+    UMA_HISTOGRAM_ENUMERATION("Media.VideoCodec.WebM", video_config.codec(),
+                              kVideoCodecMax + 1);
+  }
 
   // Drop UNKNOWN because U_H_E() uses one bucket for all values less than 1.
   if (video_config.profile() >= 0) {
@@ -1385,8 +1393,8 @@ void FFmpegDemuxer::OnFindStreamInfoDone(const PipelineStatusCB& status_cb,
     } else if (codec_type == AVMEDIA_TYPE_VIDEO) {
       VideoDecoderConfig video_config = streams_[i]->video_decoder_config();
 
-      RecordVideoCodecStats(video_config, stream->codecpar->color_range,
-                            media_log_);
+      RecordVideoCodecStats(format_context->iformat->name, video_config,
+                            stream->codecpar->color_range, media_log_);
 
       media_track = media_tracks->AddVideoTrack(video_config, track_id, "main",
                                                 track_label, track_language);