Implement select listbox using shadow DOM

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 935 matching lines @@
                         nextElement = NodeRenderingTraversal::parentElement(nextElement);
                     } while (nextElement);
                 }
                 if (matched) {
                     if (specificity)
                         *specificity = maxSpecificity;
                     return true;
                 }
             }
             break;
+        case CSSSelector::PseudoSpatialNavigationFocus:
+            return context.isUARule && matchesSpatialNavigationFocusPseudoClass(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 152 matching lines @@
     return element.document().frame() && element.document().frame()->selection().isFocusedAndActive();
 }
 
 bool SelectorChecker::matchesFocusPseudoClass(const Element& element)
 {
     if (InspectorInstrumentation::forcePseudoState(const_cast<Element*>(&element), CSSSelector::PseudoFocus))
         return true;
     return element.focused() && isFrameFocused(element);
 }
 
+bool SelectorChecker::matchesSpatialNavigationFocusPseudoClass(const Element& element)
+{
+    if (!isHTMLOptionElement(element))

[tkent, 2014/07/08 02:20:59]

nit: you can write:
return isHTMLOptionElement(element) &&
toHTMLOptionElement(element).spatialNavigationFocused() &&
isFrameFocused(element);

[keishi, 2014/07/10 09:48:03]

Done.

+        return false;
+    return toHTMLOptionElement(element).spatialNavigationFocused() && isFrameFocused(element);
+}
+
 template
 SelectorChecker::Match SelectorChecker::match(const SelectorCheckingContext&, const DOMSiblingTraversalStrategy&, MatchResult*) const;
 
 template
 SelectorChecker::Match SelectorChecker::match(const SelectorCheckingContext&, const ShadowDOMSiblingTraversalStrategy&, MatchResult*) const;
 
 }