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

Source/core/html/HTMLOptionElement.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 52 matching lines @@
     String textIndentedToRespectGroupLabel() const;
 
     void setSelectedState(bool);
 
 private:
     HTMLOptionElement(const QualifiedName&, Document*);
 
     virtual bool supportsFocus() const;
     virtual bool isFocusable() const;
     virtual bool rendererIsNeeded(const NodeRenderingContext&) { return false; }
-    virtual void attach();
-    virtual void detach();
+    virtual void attach(const AttachContext& = AttachContext()) OVERRIDE;
+    virtual void detach(const AttachContext& = AttachContext()) OVERRIDE;
 
     virtual void parseAttribute(const QualifiedName&, const AtomicString&) OVERRIDE;
 
     virtual InsertionNotificationRequest insertedInto(ContainerNode*) OVERRIDE;
     virtual void accessKeyAction(bool);
 
     virtual void childrenChanged(bool changedByParser = false, Node* beforeChange = 0, Node* afterChange = 0, int childCountDelta = 0);
 
     // <option> never has a renderer so we manually manage a cached style.
     void updateNonRenderStyle();
@@ skipping 25 matching lines @@
 inline const HTMLOptionElement* toHTMLOptionElement(const Node* node)
 {
     return static_cast<const HTMLOptionElement*>(node);
 }
 
 #endif
 
 } // namespace
 
 #endif