MSE: Record counts of detected MSE audio, video and text tracks

media/formats/webm/webm_tracks_parser.h

Index: media/formats/webm/webm_tracks_parser.h
diff --git a/media/formats/webm/webm_tracks_parser.h b/media/formats/webm/webm_tracks_parser.h
index 6286b2303e0fa02280e246393fbf6bbc997f2c1c..ae68f362e429ea7fa4753a254a37858a387bb176 100644
--- a/media/formats/webm/webm_tracks_parser.h
+++ b/media/formats/webm/webm_tracks_parser.h
@@ -78,6 +78,12 @@ class MEDIA_EXPORT WebMTracksParser : public WebMParserClient {
     return text_tracks_;
   }
 
+  int detected_audio_track_count() const { return detected_audio_track_count_; }
+
+  int detected_video_track_count() const { return detected_video_track_count_; }
+
+  int detected_text_track_count() const { return detected_text_track_count_; }
+
   // Note: Calling media_tracks() method passes the ownership of the MediaTracks
   // object from WebMTracksParser to the caller (which is typically
   // WebMStreamParser object). So this method must be called only once, after
@@ -96,21 +102,21 @@ class MEDIA_EXPORT WebMTracksParser : public WebMParserClient {
   bool OnBinary(int id, const uint8_t* data, int size) override;
   bool OnString(int id, const std::string& str) override;
 
-  int64_t track_type_;
-  int64_t track_num_;
+  int64_t track_type_ = -1;
+  int64_t track_num_ = -1;
   std::string track_name_;
   std::string track_language_;
   std::string codec_id_;
   std::vector<uint8_t> codec_private_;
-  int64_t seek_preroll_;
-  int64_t codec_delay_;
-  int64_t default_duration_;
+  int64_t seek_preroll_ = -1;
+  int64_t codec_delay_ = -1;
+  int64_t default_duration_ = -1;
   scoped_ptr<WebMContentEncodingsClient> track_content_encodings_client_;
 
-  int64_t audio_track_num_;
-  int64_t audio_default_duration_;
-  int64_t video_track_num_;
-  int64_t video_default_duration_;
+  int64_t audio_track_num_ = -1;
+  int64_t audio_default_duration_ = -1;
+  int64_t video_track_num_ = -1;
+  int64_t video_default_duration_ = -1;
   bool ignore_text_tracks_;
   TextTracks text_tracks_;
   std::set<int64_t> ignored_tracks_;
@@ -124,6 +130,9 @@ class MEDIA_EXPORT WebMTracksParser : public WebMParserClient {
   WebMVideoClient video_client_;
   VideoDecoderConfig video_decoder_config_;
 
+  int detected_audio_track_count_ = 0;
+  int detected_video_track_count_ = 0;
+  int detected_text_track_count_ = 0;
   scoped_ptr<MediaTracks> media_tracks_;
 
   DISALLOW_COPY_AND_ASSIGN(WebMTracksParser);