Add CancelChannelCreation() in protocol::Session interface.

remoting/protocol/session.h

 // Copyright (c) 2011 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_SESSION_H_
 #define REMOTING_PROTOCOL_SESSION_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 72 matching lines @@
   // callback is called with NULL if connection failed for any reason.
   // Ownership of the channel socket is given to the caller when the
   // callback is called. All channels must be destroyed before the
   // session is destroyed. Can be called only when in CONNECTING or
   // CONNECTED state.
   virtual void CreateStreamChannel(
       const std::string& name, const StreamChannelCallback& callback) = 0;
   virtual void CreateDatagramChannel(
       const std::string& name, const DatagramChannelCallback& callback) = 0;
 
+  // Cancels a pending CreateStreamChannel() or CreateDatagramChannel()
+  // operation for the named channel. If the channel creation already
+  // completed then cancelling it has no effect.
+  virtual void CancelChannelCreation(const std::string& name) = 0;
+
   // TODO(sergeyu): Remove these methods, and use CreateChannel()
   // instead.
   virtual net::Socket* control_channel() = 0;
   virtual net::Socket* event_channel() = 0;
 
   // JID of the other side.
   virtual const std::string& jid() = 0;
 
   // Configuration of the protocol that was sent or received in the
   // session-initiate jingle message. Returned pointer is valid until
@@ skipping 25 matching lines @@
   virtual void Close() = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(Session);
 };
 
 }  // namespace protocol
 }  // namespace remoting
 
 #endif  // REMOTING_PROTOCOL_SESSION_H_