Simplify data channel creation logic in WebRTC-based protocol

remoting/protocol/webrtc_transport.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef REMOTING_PROTOCOL_WEBRTC_TRANSPORT_H_
 #define REMOTING_PROTOCOL_WEBRTC_TRANSPORT_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 11 matching lines @@
 #include "third_party/webrtc/api/peerconnectioninterface.h"
 
 namespace webrtc {
 class FakeAudioDeviceModule;
 }  // namespace webrtc
 
 namespace remoting {
 namespace protocol {
 
 class TransportContext;
-class MessageChannelFactory;
 class MessagePipe;
 
 class WebrtcTransport : public Transport,
                         public webrtc::PeerConnectionObserver {
  public:
   class EventHandler {
    public:
     // Called after |peer_connection| has been created but before handshake. The
     // handler should create data channels and media streams. Renegotiation will
     // be required in two cases after this method returns:
@@ skipping 31 matching lines @@
   webrtc::PeerConnectionInterface* peer_connection() {
     return peer_connection_;
   }
   webrtc::PeerConnectionFactoryInterface* peer_connection_factory() {
     return peer_connection_factory_;
   }
   remoting::WebrtcVideoEncoderFactory* video_encoder_factory() {
     return video_encoder_factory_;
   }
 
-  // Factory for outgoing data channels. Must be used only after the transport
-  // is connected.
-  MessageChannelFactory* outgoing_channel_factory() {
-    return data_stream_adapter_.get();
-  }
+  // Creates outgoing data channel. The channel is created in CONNECTING state.
+  // The caller must wait for OnMessagePipeOpen() notification before sending
+  // any messages.
+  std::unique_ptr<MessagePipe> CreateOutgoingChannel(const std::string& name);
 
   // Transport interface.
   void Start(Authenticator* authenticator,
              SendTransportInfoCallback send_transport_info_callback) override;
   bool ProcessTransportInfo(buzz::XmlElement* transport_info) override;
   void Close(ErrorCode error);
 
  private:
   void OnLocalSessionDescriptionCreated(
       std::unique_ptr<webrtc::SessionDescriptionInterface> description,
@@ skipping 55 matching lines @@
 
   base::WeakPtrFactory<WebrtcTransport> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebrtcTransport);
 };
 
 }  // namespace protocol
 }  // namespace remoting
 
 #endif  // REMOTING_PROTOCOL_WEBRTC_TRANSPORT_H_