Move IPC::MessageFilter and router to a separate file

ppapi/proxy/host_dispatcher.h

 // Copyright (c) 2012 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_HOST_DISPATCHER_H_
 #define PPAPI_PROXY_HOST_DISPATCHER_H_
 
 #include <map>
 #include <string>
 #include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "base/process/process.h"
-#include "ipc/ipc_channel_proxy.h"
+#include "ipc/message_filter.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/proxy/dispatcher.h"
 
 struct PPB_Proxy_Private;
 
 namespace ppapi {
 
 struct Preferences;
 
 namespace proxy {
 
 class PPAPI_PROXY_EXPORT HostDispatcher : public Dispatcher {
  public:
   // This interface receives notifications about sync messages being sent by
   // the dispatcher to the plugin process. It is used to detect a hung plugin.
   //
   // Note that there can be nested sync messages, so the begin/end status
   // actually represents a stack of blocking messages.
-  class SyncMessageStatusReceiver : public IPC::ChannelProxy::MessageFilter {
+  class SyncMessageStatusReceiver : public IPC::MessageFilter {
    public:
     // Notification that a sync message is about to be sent out.
     virtual void BeginBlockOnSyncMessage() = 0;
 
     // Notification that a sync message reply was received and the dispatcher
     // is no longer blocked on a sync message.
     virtual void EndBlockOnSyncMessage() = 0;
 
    protected:
     virtual ~SyncMessageStatusReceiver() {}
@@ skipping 106 matching lines @@
  private:
   HostDispatcher* dispatcher_;
 
   DISALLOW_COPY_AND_ASSIGN(ScopedModuleReference);
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_HOST_DISPATCHER_H_