Styling option should not override option:checked UA style

Source/core/css/SelectorChecker.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
@@ skipping 27 matching lines @@
 #include "core/dom/StyleEngine.h"
 #include "core/dom/Text.h"
 #include "core/dom/shadow/InsertionPoint.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/editing/FrameSelection.h"
 #include "core/frame/LocalFrame.h"
 #include "core/html/HTMLDocument.h"
 #include "core/html/HTMLFrameElementBase.h"
 #include "core/html/HTMLInputElement.h"
 #include "core/html/HTMLOptionElement.h"
+#include "core/html/HTMLSelectElement.h"
 #include "core/html/parser/HTMLParserIdioms.h"
 #include "core/html/track/vtt/VTTElement.h"
 #include "core/inspector/InspectorInstrumentation.h"
 #include "core/page/FocusController.h"
 #include "core/page/Page.h"
 #include "core/rendering/RenderObject.h"
 #include "core/rendering/RenderScrollbar.h"
 #include "core/rendering/style/RenderStyle.h"
 #include "platform/scroll/ScrollableArea.h"
 #include "platform/scroll/ScrollbarTheme.h"
@@ skipping 887 matching lines @@
                 }
                 if (matched) {
                     if (specificity)
                         *specificity = maxSpecificity;
                     return true;
                 }
             }
             break;
         case CSSSelector::PseudoSpatialNavigationFocus:
             return context.isUARule && matchesSpatialNavigationFocusPseudoClass(element);
+        case CSSSelector::PseudoListBox:
+            return context.isUARule && matchesListBoxPseudoClass(element);
 
         case CSSSelector::PseudoHorizontal:
         case CSSSelector::PseudoVertical:
         case CSSSelector::PseudoDecrement:
         case CSSSelector::PseudoIncrement:
         case CSSSelector::PseudoStart:
         case CSSSelector::PseudoEnd:
         case CSSSelector::PseudoDoubleButton:
         case CSSSelector::PseudoSingleButton:
         case CSSSelector::PseudoNoButton:
@@ skipping 157 matching lines @@
     if (InspectorInstrumentation::forcePseudoState(const_cast<Element*>(&element), CSSSelector::PseudoFocus))
         return true;
     return element.focused() && isFrameFocused(element);
 }
 
 bool SelectorChecker::matchesSpatialNavigationFocusPseudoClass(const Element& element)
 {
     return isHTMLOptionElement(element) && toHTMLOptionElement(element).spatialNavigationFocused() && isFrameFocused(element);
 }
 
+bool SelectorChecker::matchesListBoxPseudoClass(const Element& element)
+{
+    return isHTMLSelectElement(element) && !toHTMLSelectElement(element).usesMenuList();
+}
+
 template
 SelectorChecker::Match SelectorChecker::match(const SelectorCheckingContext&, const DOMSiblingTraversalStrategy&, MatchResult*) const;
 
 template
 SelectorChecker::Match SelectorChecker::match(const SelectorCheckingContext&, const ShadowDOMSiblingTraversalStrategy&, MatchResult*) const;
 
 }