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

Source/core/html/shadow/SpinButtonElement.h

 /*
  * Copyright (C) 2006, 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google 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
@@ skipping 51 matching lines @@
     void step(int amount);
     
     virtual bool willRespondToMouseMoveEvents() OVERRIDE;
     virtual bool willRespondToMouseClickEvents() OVERRIDE;
 
     void forwardEvent(Event*);
 
 private:
     SpinButtonElement(Document*, SpinButtonOwner&);
 
-    virtual void detach();
+    virtual void detach(const AttachContext& = AttachContext()) OVERRIDE;
     virtual bool isSpinButtonElement() const { return true; }
     virtual bool isDisabledFormControl() const OVERRIDE { return shadowHost() && shadowHost()->isDisabledFormControl(); }
     virtual bool matchesReadOnlyPseudoClass() const OVERRIDE;
     virtual bool matchesReadWritePseudoClass() const OVERRIDE;
     virtual void defaultEventHandler(Event*);
     virtual void willOpenPopup() OVERRIDE;
     void doStepAction(int);
     void startRepeatingTimer();
     void stopRepeatingTimer();
     void repeatingTimerFired(Timer<SpinButtonElement>*);
@@ skipping 10 matching lines @@
 
 inline SpinButtonElement* toSpinButtonElement(Element* element)
 {
     ASSERT_WITH_SECURITY_IMPLICATION(!element || element->isSpinButtonElement());
     return static_cast<SpinButtonElement*>(element);
 }
 
 } // namespace
 
 #endif