ffmpeg reset bitstream converters on Seek

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 15e77c6aa03b1795066b28db1e92b8bb352611df..f3f87ac45ed8b794a934f477a807bf849c15932c 100644
--- a/media/filters/ffmpeg_demuxer.cc
+++ b/media/filters/ffmpeg_demuxer.cc
@@ -382,6 +382,12 @@ void FFmpegDemuxerStream::SetEndOfStream() {
 void FFmpegDemuxerStream::FlushBuffers() {
   DCHECK(task_runner_->BelongsToCurrentThread());
   DCHECK(read_cb_.is_null()) << "There should be no pending read";
+
+  // H264 requires that we resend the header after flush.
+  // Reset its bitstream for converter to do so.
+  // This is related to chromium issue 140371 (http://crbug.com/140371).
+  ResetBitstreamConverter();
+
   buffer_queue_.Clear();
   end_of_stream_ = false;
   last_packet_timestamp_ = kNoTimestamp();
@@ -434,6 +440,16 @@ void FFmpegDemuxerStream::EnableBitstreamConverter() {
 #endif
 }
 
+void FFmpegDemuxerStream::ResetBitstreamConverter() {
+#if defined(USE_PROPRIETARY_CODECS)
+  if (!bitstream_converter_enabled_ || !bitstream_converter_)
+    return;
+
+  bitstream_converter_.reset(
+      new FFmpegH264ToAnnexBBitstreamConverter(stream_->codec));
+#endif  // defined(USE_PROPRIETARY_CODECS)
+}
+
 bool FFmpegDemuxerStream::SupportsConfigChanges() { return false; }
 
 AudioDecoderConfig FFmpegDemuxerStream::audio_decoder_config() {