:hover style not applied on hover if its display property is different from original style's

Source/core/html/PluginDocument.h

 /*
  * Copyright (C) 2006, 2008, 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 26 matching lines @@
     static PassRefPtr<PluginDocument> create(Frame* frame, const KURL& url)
     {
         return adoptRef(new PluginDocument(frame, url));
     }
 
     void setPluginNode(Node* pluginNode) { m_pluginNode = pluginNode; }
 
     Widget* pluginWidget();
     Node* pluginNode();
 
-    virtual void detach() OVERRIDE;
+    virtual void detach(const AttachContext& = AttachContext()) OVERRIDE;
 
     void cancelManualPluginLoad();
 
     bool shouldLoadPluginManually() { return m_shouldLoadPluginManually; }
 
 private:
     PluginDocument(Frame*, const KURL&);
 
     virtual PassRefPtr<DocumentParser> createParser() OVERRIDE;
         
@@ skipping 14 matching lines @@
     ASSERT_WITH_SECURITY_IMPLICATION(!document || document->isPluginDocument());
     return static_cast<const PluginDocument*>(document);
 }
 
 // This will catch anyone doing an unnecessary cast.
 void toPluginDocument(const PluginDocument*);
     
 }
 
 #endif // PluginDocument_h