Use the new versions of OnAddStream/OnRemoveStream in objc binding.

webrtc/sdk/objc/Framework/Classes/RTCPeerConnection+Private.h

 /*
  *  Copyright 2015 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 11 matching lines @@
  */
 class PeerConnectionDelegateAdapter : public PeerConnectionObserver {
 
  public:
   PeerConnectionDelegateAdapter(RTCPeerConnection *peerConnection);
   virtual ~PeerConnectionDelegateAdapter();
 
   void OnSignalingChange(
       PeerConnectionInterface::SignalingState new_state) override;
 
-  void OnAddStream(MediaStreamInterface *stream) override;
+  void OnAddStream(rtc::scoped_refptr<MediaStreamInterface> stream) override;
 
-  void OnRemoveStream(MediaStreamInterface *stream) override;
+  void OnRemoveStream(rtc::scoped_refptr<MediaStreamInterface> stream) override;
 
-  void OnDataChannel(DataChannelInterface *data_channel) override;
+  void OnDataChannel(
+      rtc::scoped_refptr<DataChannelInterface> data_channel) override;
 
   void OnRenegotiationNeeded() override;
 
   void OnIceConnectionChange(
       PeerConnectionInterface::IceConnectionState new_state) override;
 
   void OnIceGatheringChange(
       PeerConnectionInterface::IceGatheringState new_state) override;
 
   void OnIceCandidate(const IceCandidateInterface *candidate) override;
@@ skipping 50 matching lines @@
     (webrtc::PeerConnectionInterface::IceGatheringState)nativeState;
 
 + (NSString *)stringForIceGatheringState:(RTCIceGatheringState)state;
 
 + (webrtc::PeerConnectionInterface::StatsOutputLevel)
     nativeStatsOutputLevelForLevel:(RTCStatsOutputLevel)level;
 
 @end
 
 NS_ASSUME_NONNULL_END