Fixing gcc 4.7 building problems.

ipc/ipc_channel.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_H_
 #define IPC_IPC_CHANNEL_H_
 #pragma once
 
 #include <string>
 
+#if defined(OS_POSIX)
+#include <sys/types.h>
+#endif
+
 #include "base/compiler_specific.h"
 #include "base/process.h"
 #include "ipc/ipc_channel_handle.h"
 #include "ipc/ipc_message.h"
 
 namespace IPC {
 
 //------------------------------------------------------------------------------
 // See
 // http://www.chromium.org/developers/design-documents/inter-process-communication
@@ skipping 201 matching lines @@
 
  private:
   // PIMPL to which all channel calls are delegated.
   class ChannelImpl;
   ChannelImpl *channel_impl_;
 };
 
 }  // namespace IPC
 
 #endif  // IPC_IPC_CHANNEL_H_