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

webrtc/video/video_stream_decoder.h

Index: webrtc/video/video_stream_decoder.h
diff --git a/webrtc/video/video_stream_decoder.h b/webrtc/video/video_stream_decoder.h
index 4bca3edfc348f5c70adde8cb224649fa056ea302..b670b12659c1a8618ca686a611b9691f6a7355c4 100644
--- a/webrtc/video/video_stream_decoder.h
+++ b/webrtc/video/video_stream_decoder.h
@@ -59,7 +59,8 @@
 
   // Implements VCMReceiveCallback.
   int32_t FrameToRender(VideoFrame& video_frame,
-                        rtc::Optional<uint8_t> qp) override;
+                        rtc::Optional<uint8_t> qp,
+                        VideoContentType content_type) override;
   int32_t ReceivedDecodedReferenceFrame(const uint64_t picture_id) override;
   void OnIncomingPayloadType(int payload_type) override;
   void OnDecoderImplementationName(const char* implementation_name) override;