Use scoped_refptr for On(Add|Remove)Stream and OnDataChannel.

webrtc/api/test/peerconnectiontestwrapper.cc

Index: webrtc/api/test/peerconnectiontestwrapper.cc
diff --git a/webrtc/api/test/peerconnectiontestwrapper.cc b/webrtc/api/test/peerconnectiontestwrapper.cc
index 717c48af13767634c0dcf993b352e4085deeb707..8f65c68dddfef8de18928601f572ee5dd4ba0d76 100644
--- a/webrtc/api/test/peerconnectiontestwrapper.cc
+++ b/webrtc/api/test/peerconnectiontestwrapper.cc
@@ -92,7 +92,8 @@ PeerConnectionTestWrapper::CreateDataChannel(
   return peer_connection_->CreateDataChannel(label, &init);
 }
 
-void PeerConnectionTestWrapper::OnAddStream(MediaStreamInterface* stream) {
+void PeerConnectionTestWrapper::OnAddStream(
+    rtc::scoped_refptr<MediaStreamInterface> stream) {
   LOG(LS_INFO) << "PeerConnectionTestWrapper " << name_
                << ": OnAddStream";
   // TODO(ronghuawu): support multiple streams.
@@ -112,7 +113,7 @@ void PeerConnectionTestWrapper::OnIceCandidate(
 }
 
 void PeerConnectionTestWrapper::OnDataChannel(
-    webrtc::DataChannelInterface* data_channel) {
+    rtc::scoped_refptr<webrtc::DataChannelInterface> data_channel) {
   SignalOnDataChannel(data_channel);
 }