Move responsibility for RTP header extensions on video receive.

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 cee62d297c796c4fec7d42ddfb7e9ff4418103fe..514c5b6b0a927e426d9a62430cd49acdf3082209 100644
--- a/webrtc/video/video_receive_stream.cc
+++ b/webrtc/video/video_receive_stream.cc
@@ -96,15 +96,7 @@ std::string VideoReceiveStream::Config::Rtp::ToString() const {
   for (auto& kv : rtx_payload_types) {
     ss << kv.first << " (apt) -> " << kv.second << " (pt), ";
   }
-  ss << '}';
-  ss << ", extensions: [";
-  for (size_t i = 0; i < extensions.size(); ++i) {
-    ss << extensions[i].ToString();
-    if (i != extensions.size() - 1)
-      ss << ", ";
-  }
-  ss << ']';
-  ss << '}';
+  ss << "}}";
   return ss.str();
 }