Handle closed mode shadow for /deep/ and ::shadow selectors

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 414 matching lines @@
             if (context.selector->relationIsAffectedByPseudoContent()) {
                 for (Element* element = context.element; element; element = element->parentOrShadowHostElement()) {
                     if (matchForShadowDistributed(nextContext, *element, result) == SelectorMatches)
                         return SelectorMatches;
                 }
                 return SelectorFailsCompletely;
             }
 
             nextContext.isSubSelector = false;
             nextContext.inRightmostCompound = false;
-            for (nextContext.element = context.element->parentOrShadowHostElement(); nextContext.element; nextContext.element = nextContext.element->parentOrShadowHostElement()) {
+
+            Element* element = context.element;

[hayato, 2015/08/20 03:47:11]

I'm afraid that it would be difficult to read what this while loop does.

Could you refactor this loop so that it would be easier to read the intention?

Like before this CL https://codereview.chromium.org/1143003008/, using static
inline function.

[kochi, 2015/08/20 06:04:26]

Done.

+            while (true) {
+                if (element->parentNode() && element->parentNode()->isShadowRoot()) {
+                    if (!toShadowRoot(element->parentNode())->isOpen())
+                        break;
+                }
+                element = element->parentOrShadowHostElement();
+                if (!element)
+                    break;
+
+                nextContext.element = element;
                 Match match = matchSelector(nextContext, result);
                 if (match == SelectorMatches || match == SelectorFailsCompletely)
                     return match;
                 if (nextSelectorExceedsScope(nextContext))
-                    return SelectorFailsCompletely;
+                    break;
             }
             return SelectorFailsCompletely;
         }
 
     case CSSSelector::SubSelector:
         ASSERT_NOT_REACHED();
     }
 
     ASSERT_NOT_REACHED();
     return SelectorFailsCompletely;
@@ skipping 726 matching lines @@
 }
 
 bool SelectorChecker::matchesFocusPseudoClass(const Element& element)
 {
     if (InspectorInstrumentation::forcePseudoState(const_cast<Element*>(&element), CSSSelector::PseudoFocus))
         return true;
     return element.focused() && isFrameFocused(element);
 }
 
 }