ppapi: Cleanup class/struct forward declarations

ppapi/host/ppapi_host.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_HOST_PPAPI_HOST_H_
 #define PPAPI_HOST_PPAPI_HOST_H_
 
 #include <map>
 #include <memory>
 #include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "ipc/ipc_listener.h"
 #include "ipc/ipc_sender.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_resource.h"
 #include "ppapi/host/ppapi_host_export.h"
 #include "ppapi/shared_impl/ppapi_permissions.h"
 
 namespace ppapi {
 
 namespace proxy {
 class ResourceMessageCallParams;
-class ResourceMessageReplyParams;
 class SerializedHandle;
 }
 
 namespace host {
 
 class HostFactory;
 struct HostMessageContext;
 class InstanceMessageFilter;
 struct ReplyMessageContext;
 class ResourceHost;
@@ skipping 105 matching lines @@
   PendingHostResourceMap pending_resource_hosts_;
   int next_pending_resource_host_id_;
 
   DISALLOW_COPY_AND_ASSIGN(PpapiHost);
 };
 
 }  // namespace host
 }  // namespace ppapi
 
 #endif  // PPAPI_HOST_PPAPIE_HOST_H_