ipc: Add the inner class OutputElement to Channel.

ipc/ipc_channel_win.h

 // Copyright (c) 2012 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 IPC_IPC_CHANNEL_WIN_H_
 #define IPC_IPC_CHANNEL_WIN_H_
 
 #include "ipc/ipc_channel.h"
 
 #include <stdint.h>
@@ skipping 89 matching lines @@
   // this queue are placed in the output_queue_. The double queue is
   // unfortunate, but is necessary because messages with brokerable attachments
   // can generate multiple messages to be sent (possibly from other channels).
   // Some of these generated messages cannot be sent until |peer_pid_| has been
   // configured.
   // As soon as |peer_pid| has been configured, there is no longer any need for
   // |prelim_queue_|. All messages are flushed, and no new messages are added.
   std::queue<Message*> prelim_queue_;
 
   // Messages to be sent are queued here.
-  std::queue<Message*> output_queue_;
+  std::queue<OutputElement*> output_queue_;
 
   // In server-mode, we have to wait for the client to connect before we
   // can begin reading.  We make use of the input_state_ when performing
   // the connect operation in overlapped mode.
   bool waiting_connect_;
 
   // This flag is set when processing incoming messages.  It is used to
   // avoid recursing through ProcessIncomingMessages, which could cause
   // problems.  TODO(darin): make this unnecessary
   bool processing_incoming_;
@@ skipping 15 matching lines @@
   // |broker_| must outlive this instance.
   AttachmentBroker* broker_;
 
   base::WeakPtrFactory<ChannelWin> weak_factory_;
   DISALLOW_COPY_AND_ASSIGN(ChannelWin);
 };
 
 }  // namespace IPC
 
 #endif  // IPC_IPC_CHANNEL_WIN_H_