Decouple Blimp transport output from BlimpConnections using MessagePort.

blimp/net/blimp_connection.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 BLIMP_NET_BLIMP_CONNECTION_H_
 #define BLIMP_NET_BLIMP_CONNECTION_H_
 
 #include <memory>
 
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "blimp/net/blimp_net_export.h"
 #include "blimp/net/connection_error_observer.h"
 
 namespace blimp {
 
 class BlimpMessageProcessor;
 class BlimpMessagePump;
 class BlimpMessageSender;
-class PacketReader;
-class PacketWriter;
+class MessagePort;
 
 // Encapsulates the state and logic used to exchange BlimpMessages over
 // a network connection.
 class BLIMP_NET_EXPORT BlimpConnection : public ConnectionErrorObserver {
  public:
-  BlimpConnection(std::unique_ptr<PacketReader> reader,
-                  std::unique_ptr<PacketWriter> writer);
-
+  explicit BlimpConnection(std::unique_ptr<MessagePort> message_port);
   ~BlimpConnection() override;
 
   // Adds |observer| to the connection's error observer list.
   virtual void AddConnectionErrorObserver(ConnectionErrorObserver* observer);
 
   // Removes |observer| from the connection's error observer list.
   virtual void RemoveConnectionErrorObserver(ConnectionErrorObserver* observer);
 
   // Sets the processor which will take incoming messages for this connection.
   // Can be set multiple times, but previously set processors are discarded.
   // Caller retains the ownership of |processor|.
   virtual void SetIncomingMessageProcessor(BlimpMessageProcessor* processor);
 
   // Gets a processor for BrowserSession->BlimpConnection message routing.
   virtual BlimpMessageProcessor* GetOutgoingMessageProcessor();
 
  protected:
   class EndConnectionFilter;
   friend class EndConnectionFilter;
 
   BlimpConnection();
 
   // ConnectionErrorObserver implementation.
   void OnConnectionError(int error) override;
 
  private:
-  std::unique_ptr<PacketReader> reader_;
+  std::unique_ptr<MessagePort> message_port_;
   std::unique_ptr<BlimpMessagePump> message_pump_;
-  std::unique_ptr<PacketWriter> writer_;
   std::unique_ptr<BlimpMessageSender> outgoing_msg_processor_;
   base::ObserverList<ConnectionErrorObserver> error_observers_;
   std::unique_ptr<EndConnectionFilter> end_connection_filter_;
 
   DISALLOW_COPY_AND_ASSIGN(BlimpConnection);
 };
 
 }  // namespace blimp
 
 #endif  // BLIMP_NET_BLIMP_CONNECTION_H_