[Blimp Net] Add EngineAuthHandler.

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 "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "blimp/net/blimp_net_export.h"
 
 namespace blimp {
 
 class BlimpMessageProcessor;
 class BlimpMessagePump;
 class ConnectionErrorObserver;
 class PacketReader;
 class PacketWriter;
 
 // Encapsulates the state and logic used to exchange BlimpMessages over
 // a network connection.
 class BLIMP_NET_EXPORT BlimpConnection {
  public:
   BlimpConnection(scoped_ptr<PacketReader> reader,
                   scoped_ptr<PacketWriter> writer);
 
   virtual ~BlimpConnection();
 
   // Lets |observer| know when the network connection encounters an error.
-  void SetConnectionErrorObserver(ConnectionErrorObserver* observer);
+  virtual void SetConnectionErrorObserver(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|.
-  void SetIncomingMessageProcessor(BlimpMessageProcessor* processor);
+  virtual void SetIncomingMessageProcessor(BlimpMessageProcessor* processor);
 
   // Gets a processor for BrowserSession->BlimpConnection message routing.
-  BlimpMessageProcessor* GetOutgoingMessageProcessor() const;
+  virtual BlimpMessageProcessor* GetOutgoingMessageProcessor() const;
+
+ protected:
+  BlimpConnection();
 
  private:
   scoped_ptr<PacketReader> reader_;
   scoped_ptr<BlimpMessagePump> message_pump_;
   scoped_ptr<PacketWriter> writer_;
   scoped_ptr<BlimpMessageProcessor> outgoing_msg_processor_;
 
   DISALLOW_COPY_AND_ASSIGN(BlimpConnection);
 };
 
 }  // namespace blimp
 
 #endif  // BLIMP_NET_BLIMP_CONNECTION_H_