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

webrtc/api/peerconnectioninterface_unittest.cc

Index: webrtc/api/peerconnectioninterface_unittest.cc
diff --git a/webrtc/api/peerconnectioninterface_unittest.cc b/webrtc/api/peerconnectioninterface_unittest.cc
index 1386e8c2106cf75f0a807ffdd814135ec494b3f1..6a93cb7900b28ab157fe197b827c9a34f4fbeb41 100644
--- a/webrtc/api/peerconnectioninterface_unittest.cc
+++ b/webrtc/api/peerconnectioninterface_unittest.cc
@@ -454,16 +454,18 @@ class MockPeerConnectionObserver : public PeerConnectionObserver {
     return remote_streams_->find(label);
   }
   StreamCollectionInterface* remote_streams() const { return remote_streams_; }
-  void OnAddStream(MediaStreamInterface* stream) override {
+  void OnAddStream(rtc::scoped_refptr<MediaStreamInterface> stream) override {
     last_added_stream_ = stream;
     remote_streams_->AddStream(stream);
   }
-  void OnRemoveStream(MediaStreamInterface* stream) override {
+  void OnRemoveStream(
+      rtc::scoped_refptr<MediaStreamInterface> stream) override {
     last_removed_stream_ = stream;
     remote_streams_->RemoveStream(stream);
   }
   void OnRenegotiationNeeded() override { renegotiation_needed_ = true; }
-  void OnDataChannel(DataChannelInterface* data_channel) override {
+  void OnDataChannel(
+      rtc::scoped_refptr<DataChannelInterface> data_channel) override {
     last_datachannel_ = data_channel;
   }