content: Cleanup class/struct forward declarations

content/renderer/pepper/plugin_module.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 CONTENT_RENDERER_PEPPER_PLUGIN_MODULE_H_
 #define CONTENT_RENDERER_PEPPER_PLUGIN_MODULE_H_
 
 #include <map>
 #include <memory>
 #include <set>
@@ skipping 16 matching lines @@
 typedef void* NPIdentifier;
 
 class GURL;
 
 namespace base {
 class FilePath;
 }
 
 namespace ppapi {
 class CallbackTracker;
-class WebKitForwarding;
 }  // namespace ppapi
 
 namespace IPC {
 struct ChannelHandle;
 }
 
 namespace blink {
 class WebPluginContainer;
 }  // namespace blink
 
@@ skipping 222 matching lines @@
   PluginInstanceSet instances_;
 
   PP_Bool (*reserve_instance_id_)(PP_Module, PP_Instance);
 
   DISALLOW_COPY_AND_ASSIGN(PluginModule);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_PEPPER_PLUGIN_MODULE_H_