Report timing frames info in GetStats.

webrtc/video/video_receive_stream.cc

Index: webrtc/video/video_receive_stream.cc
diff --git a/webrtc/video/video_receive_stream.cc b/webrtc/video/video_receive_stream.cc
index acc497b616433e771a2259247f1360cbd1619095..88a70a1b5a0e6c2e9ad352b7455e9c4df57a5a7f 100644
--- a/webrtc/video/video_receive_stream.cc
+++ b/webrtc/video/video_receive_stream.cc
@@ -132,7 +132,9 @@ std::string VideoReceiveStream::Stats::ToString(int64_t time_ms) const {
   ss << "max_ext_seq: " << rtcp_stats.extended_max_sequence_number << ", ";
   ss << "nack: " << rtcp_packet_type_counts.nack_packets << ", ";
   ss << "fir: " << rtcp_packet_type_counts.fir_packets << ", ";
-  ss << "pli: " << rtcp_packet_type_counts.pli_packets;
+  ss << "pli: " << rtcp_packet_type_counts.pli_packets << ", ";
+  ss << "timing_frame_info: " << (
+      timing_frame_info ? timing_frame_info->ToString() : "N/A");
   ss << '}';
   return ss.str();
 }