ipc: Remove unnecessary attachment broker plumbing.

ipc/ipc_channel_factory.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_FACTORY_H_
 #define IPC_IPC_CHANNEL_FACTORY_H_
 
 #include <string>
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "ipc/ipc_channel.h"
 
 namespace IPC {
 
-class AttachmentBroker;
-
 // Encapsulates how a Channel is created. A ChannelFactory can be
 // passed to the constructor of ChannelProxy or SyncChannel to tell them
 // how to create underlying channel.
 class IPC_EXPORT ChannelFactory {
  public:
   // Creates a factory for "native" channel built through
   // IPC::Channel::Create().
   static scoped_ptr<ChannelFactory> Create(const ChannelHandle& handle,
-                                           Channel::Mode mode,
-                                           AttachmentBroker* broker);
+                                           Channel::Mode mode);
 
   virtual ~ChannelFactory() { }
   virtual std::string GetName() const = 0;
   virtual scoped_ptr<Channel> BuildChannel(Listener* listener) = 0;
 };
 
 }  // namespace IPC
 
 #endif  // IPC_IPC_CHANNEL_FACTORY_H_