IPC: Get rid of FileDescriptor usage from FileDescriptorSet and Message

ipc/mojo/ipc_channel_mojo.h

 // Copyright 2014 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_MOJO_H_
 #define IPC_IPC_CHANNEL_MOJO_H_
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 69 matching lines @@
 
 #if defined(OS_POSIX) && !defined(OS_NACL)
   virtual int GetClientFileDescriptor() const OVERRIDE;
   virtual int TakeClientFileDescriptor() OVERRIDE;
 
   // These access protected API of IPC::Message, which has ChannelMojo
   // as a friend class.
   static MojoResult WriteToFileDescriptorSet(
       const std::vector<MojoHandle>& handle_buffer,
       Message* message);
-  static MojoResult ReadFromFileDescriptorSet(const Message& message,
+  static MojoResult ReadFromFileDescriptorSet(Message* message,
                                               std::vector<MojoHandle>* handles);
 
 #endif  // defined(OS_POSIX) && !defined(OS_NACL)
 
   // Called from MessagePipeReader implementations
   void OnMessageReceived(Message& message);
   void OnConnected(mojo::ScopedMessagePipeHandle pipe);
   void OnPipeClosed(internal::MessagePipeReader* reader);
   void OnPipeError(internal::MessagePipeReader* reader);
   void set_peer_pid(base::ProcessId pid) { peer_pid_ = pid; }
@@ skipping 28 matching lines @@
   ScopedVector<Message> pending_messages_;
 
   base::WeakPtrFactory<ChannelMojo> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ChannelMojo);
 };
 
 }  // namespace IPC
 
 #endif  // IPC_IPC_CHANNEL_MOJO_H_