Revert of Adds associated interface support to IPC::Channel

ipc/ipc_channel_common.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 "build/build_config.h"
 #include "ipc/ipc_channel.h"
 #include "ipc/ipc_channel_mojo.h"
 #include "mojo/public/cpp/system/message_pipe.h"
 
 namespace IPC {
@@ skipping 66 matching lines @@
   mojo::MessagePipe message_pipe;
   *handle0 = ChannelHandle(name);
   handle0->mojo_handle = message_pipe.handle0.release();
   *handle1 = ChannelHandle(name);
   handle1->mojo_handle = message_pipe.handle1.release();
 }
 
 Channel::~Channel() {
 }
 
-Channel::AssociatedInterfaceSupport* Channel::GetAssociatedInterfaceSupport() {
-  return nullptr;
-}
-
 bool Channel::IsSendThreadSafe() const {
   return false;
 }
 
 void Channel::OnSetAttachmentBrokerEndpoint() {
   CHECK(!did_start_connect_);
 }
 
 void Channel::WillConnect() {
   did_start_connect_ = true;
 }
 
 }  // namespace IPC