Move IPC::MessageFilter and router to a separate file

ppapi/proxy/plugin_message_filter.h

 // Copyright (c) 2011 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 PPAPI_PROXY_PLUGIN_MESSAGE_FILTER_H_
 #define PPAPI_PROXY_PLUGIN_MESSAGE_FILTER_H_
 
 #include <set>
 
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
-#include "ipc/ipc_channel_proxy.h"
 #include "ipc/ipc_sender.h"
+#include "ipc/message_filter.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/proxy/ppapi_proxy_export.h"
 
 namespace ppapi {
 namespace proxy {
 
 class ResourceMessageReplyParams;
 class ResourceReplyThreadRegistrar;
 
 // Listens for messages on the I/O thread of the plugin and handles some of
 // them to avoid needing to block on the plugin.
 //
 // There is one instance of this class for each renderer channel (same as for
 // the PluginDispatchers).
-class PPAPI_PROXY_EXPORT PluginMessageFilter
-    : public IPC::ChannelProxy::MessageFilter,
-      public IPC::Sender {
+class PPAPI_PROXY_EXPORT PluginMessageFilter : public IPC::MessageFilter,
+                                               public IPC::Sender {
  public:
   // |seen_instance_ids| is a pointer to a set that will be used to uniquify
   // PP_Instances across all renderer channels. The same pointer should be
   // passed to each MessageFilter to ensure uniqueness, and the value should
   // outlive this class. It could be NULL if this filter is for a browser
   // channel.
   // |thread_registrar| is used to look up handling threads for resource
   // reply messages. It shouldn't be NULL.
   PluginMessageFilter(
       std::set<PP_Instance>* seen_instance_ids,
@@ skipping 34 matching lines @@
 
   // The IPC channel to the renderer. May be NULL if we're not currently
   // attached as a filter.
   IPC::Channel* channel_;
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_PLUGIN_MESSAGE_FILTER_H_