Add read support of RtpStreamId/RepairedRtpStreamId header extensions.

webrtc/modules/rtp_rtcp/source/rtp_utility.cc

Index: webrtc/modules/rtp_rtcp/source/rtp_utility.cc
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_utility.cc b/webrtc/modules/rtp_rtcp/source/rtp_utility.cc
index def431f1709499993bac608a993aa0c49e33bc1b..9f9599d91e34ead5f574d7593b21a10a16221deb 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_utility.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtp_utility.cc
@@ -446,6 +446,14 @@ void RtpHeaderParser::ParseOneByteExtensionHeader(
               max_playout_delay * PlayoutDelayLimits::kGranularityMs;
           break;
         }
+        case kRtpExtensionRtpStreamId: {
+          header->extension.stream_id.Set(ptr, len + 1);
+          break;
+        }
+        case kRtpExtensionRepairedRtpStreamId: {
+          header->extension.repaired_stream_id.Set(ptr, len + 1);
+          break;
+        }
         case kRtpExtensionNone:
         case kRtpExtensionNumberOfExtensions: {
           RTC_NOTREACHED() << "Invalid extension type: " << type;