Add live mode detection in WebM MediaSource parser.

media/formats/webm/webm_tracks_parser.cc

Index: media/formats/webm/webm_tracks_parser.cc
diff --git a/media/formats/webm/webm_tracks_parser.cc b/media/formats/webm/webm_tracks_parser.cc
index ed7fd521be106861051fc7b77a97fc0f69007880..80c180f86bdb65b17320f6fbbe1cf6479f11042d 100644
--- a/media/formats/webm/webm_tracks_parser.cc
+++ b/media/formats/webm/webm_tracks_parser.cc
@@ -43,8 +43,11 @@ static base::TimeDelta PrecisionCappedDefaultDuration(
   return base::TimeDelta::FromMicroseconds(mult);
 }
 
-WebMTracksParser::WebMTracksParser(const LogCB& log_cb, bool ignore_text_tracks)
-    : track_type_(-1),
+WebMTracksParser::WebMTracksParser(const LogCB& log_cb,
+                                   bool ignore_text_tracks,
+                                   bool live_mode)
+    : live_mode_(live_mode),
+      track_type_(-1),
       track_num_(-1),
       track_uid_(-1),
       seek_preroll_(-1),
@@ -228,7 +231,7 @@ bool WebMTracksParser::OnListEnd(int id) {
         DCHECK(!video_decoder_config_.IsValidConfig());
         if (!video_client_.InitializeConfig(
                 codec_id_, codec_private_, !video_encryption_key_id_.empty(),
-                &video_decoder_config_)) {
+                live_mode_, &video_decoder_config_)) {
           return false;
         }
       } else {