Revert 276939 "Decouple IPC::MessageFilter from IPC::Channel"

ipc/message_filter.cc

 // 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.
 
 #include "ipc/message_filter.h"
 
 #include "base/memory/ref_counted.h"
 #include "ipc/ipc_channel.h"
 
 namespace IPC {
 
 MessageFilter::MessageFilter() {}
 
-void MessageFilter::OnFilterAdded(Sender* sender) {}
+void MessageFilter::OnFilterAdded(Channel* channel) {}
 
 void MessageFilter::OnFilterRemoved() {}
 
 void MessageFilter::OnChannelConnected(int32 peer_pid) {}
 
 void MessageFilter::OnChannelError() {}
 
 void MessageFilter::OnChannelClosing() {}
 
 bool MessageFilter::OnMessageReceived(const Message& message) {
   return false;
 }
 
 bool MessageFilter::GetSupportedMessageClasses(
     std::vector<uint32>* /*supported_message_classes*/) const {
   return false;
 }
 
 MessageFilter::~MessageFilter() {}
 
 }  // namespace IPC