Reland of Add QP for FFmpeg H264 decoder.

webrtc/modules/video_coding/codecs/h264/h264_decoder_impl.h

Index: webrtc/modules/video_coding/codecs/h264/h264_decoder_impl.h
diff --git a/webrtc/modules/video_coding/codecs/h264/h264_decoder_impl.h b/webrtc/modules/video_coding/codecs/h264/h264_decoder_impl.h
index fc730a4f4d898aa81efca9ca18f1b20d7237fbfb..44c2acb2e075046c1504df2bcec06bee0666ffb0 100644
--- a/webrtc/modules/video_coding/codecs/h264/h264_decoder_impl.h
+++ b/webrtc/modules/video_coding/codecs/h264/h264_decoder_impl.h
@@ -20,6 +20,7 @@
 #include "third_party/ffmpeg/libavcodec/avcodec.h"
 }  // extern "C"
 
+#include "webrtc/common_video/h264/h264_bitstream_parser.h"
 #include "webrtc/common_video/include/i420_buffer_pool.h"
 
 namespace webrtc {
@@ -77,6 +78,8 @@
 
   bool has_reported_init_;
   bool has_reported_error_;
+
+  webrtc::H264BitstreamParser h264_bitstream_parser_;
 };
 
 }  // namespace webrtc