Add content type information to encoded images and corresponding rtp extension header

webrtc/modules/rtp_rtcp/source/rtp_receiver_video.cc

Index: webrtc/modules/rtp_rtcp/source/rtp_receiver_video.cc
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_receiver_video.cc b/webrtc/modules/rtp_rtcp/source/rtp_receiver_video.cc
index d6c5e5c29b6ac4667f80681c0df5322d645747a1..8fe50e4940df732f07d69dd8ada94a8bf36c3125 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_receiver_video.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtp_receiver_video.cc
@@ -90,6 +90,7 @@ int32_t RTPReceiverVideo::ParseRtpPacket(WebRtcRTPHeader* rtp_header,
   rtp_header->frameType = parsed_payload.frame_type;
   rtp_header->type = parsed_payload.type;
   rtp_header->type.Video.rotation = kVideoRotation_0;
+  rtp_header->type.Video.content_type = VideoContentType::kUnspecified;
 
   // Retrieve the video rotation information.
   if (rtp_header->header.extension.hasVideoRotation) {
@@ -97,6 +98,11 @@ int32_t RTPReceiverVideo::ParseRtpPacket(WebRtcRTPHeader* rtp_header,
         rtp_header->header.extension.videoRotation;
   }
 
+  if (rtp_header->header.extension.hasVideoContentType) {
+    rtp_header->type.Video.content_type =
+        rtp_header->header.extension.videoContentType;
+  }
+
   rtp_header->type.Video.playout_delay =
       rtp_header->header.extension.playout_delay;