SelectorChecker should update scope and behaviorAtBoundary for /content/ in SharingRules mode

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 338 matching lines @@
 
     const ContainerNode* scope = nextContext.scope;
     BehaviorAtBoundary behaviorAtBoundary = nextContext.behaviorAtBoundary;
 
     collectDestinationInsertionPoints(*element, insertionPoints);
     for (size_t i = 0; i < insertionPoints.size(); ++i) {
         nextContext.element = insertionPoints[i];
 
         // If a given scope is a shadow host of an insertion point but behaviorAtBoundary doesn't have ScopeIsShadowHost,
         // we need to update behaviorAtBoundary to make selectors like ":host > ::content" work correctly.
-        if (scope == insertionPoints[i]->containingShadowRoot()->shadowHost() && !(behaviorAtBoundary & ScopeIsShadowHost))
+        if (m_mode == SharingRules) {
+            nextContext.behaviorAtBoundary = static_cast<BehaviorAtBoundary>(behaviorAtBoundary | ScopeIsShadowHost);
+            nextContext.scope = insertionPoints[i]->containingShadowRoot()->shadowHost();
+        } else if (scope == insertionPoints[i]->containingShadowRoot()->shadowHost() && !(behaviorAtBoundary & ScopeIsShadowHost))
             nextContext.behaviorAtBoundary = static_cast<BehaviorAtBoundary>(behaviorAtBoundary | ScopeIsShadowHost);
         else
             nextContext.behaviorAtBoundary = behaviorAtBoundary;
 
         nextContext.isSubSelector = false;
         nextContext.elementStyle = 0;
         if (match(nextContext, siblingTraversalStrategy, result) == SelectorMatches)
             return SelectorMatches;
     }
-    return SelectorFailsCompletely;
+    return SelectorFailsLocally;
 }
 
 static inline bool containsHTMLSpace(const AtomicString& string)
 {
     for (unsigned i = 0; i < string.length(); i++)
         if (isHTMLSpace<UChar>(string[i]))
             return true;
     return false;
 }
 
@@ skipping 134 matching lines @@
             subContext.isSubSelector = true;
             ASSERT(selector.selectorList());
             for (subContext.selector = selector.selectorList()->first(); subContext.selector; subContext.selector = subContext.selector->tagHistory()) {
                 // :not cannot nest. I don't really know why this is a
                 // restriction in CSS3, but it is, so let's honor it.
                 // the parser enforces that this never occurs
                 ASSERT(subContext.selector->pseudoType() != CSSSelector::PseudoNot);
                 // We select between :visited and :link when applying. We don't know which one applied (or not) yet.
                 if (subContext.selector->pseudoType() == CSSSelector::PseudoVisited || (subContext.selector->pseudoType() == CSSSelector::PseudoLink && subContext.visitedMatchType == VisitedMatchEnabled))
                     return true;
+                // context.scope is not available if m_mode == SharingRules.
+                // We cannot determine whether :host or :scope matches a given element or not.
+                if (m_mode == SharingRules && (subContext.selector->isHostPseudoClass() || subContext.selector->pseudoType() == CSSSelector::PseudoScope))
+                    return true;
                 if (!checkOne(subContext, DOMSiblingTraversalStrategy()))
                     return true;
             }
         } else if (context.hasScrollbarPseudo) {
             // CSS scrollbars match a specific subset of pseudo classes, and they have specialized rules for each
             // (since there are no elements involved).
             return checkScrollbarPseudoClass(context, &element.document(), selector);
         } else if (context.hasSelectionPseudo) {
             if (selector.pseudoType() == CSSSelector::PseudoWindowInactive)
                 return !element.document().page()->focusController().isActive();
@@ skipping 319 matching lines @@
         case CSSSelector::PseudoOutOfRange:
             element.document().setContainsValidityStyleRules();
             return element.isOutOfRange();
         case CSSSelector::PseudoFutureCue:
             return (element.isVTTElement() && !toVTTElement(element).isPastNode());
         case CSSSelector::PseudoPastCue:
             return (element.isVTTElement() && toVTTElement(element).isPastNode());
 
         case CSSSelector::PseudoScope:
             {
+                if (m_mode == SharingRules)
+                    return true;
                 const Node* contextualReferenceNode = !context.scope ? element.document().documentElement() : context.scope;
                 if (element == contextualReferenceNode)
                     return true;
                 break;
             }
 
         case CSSSelector::PseudoUnresolved:
             if (element.isUnresolvedCustomElement())
                 return true;
             break;
 
         case CSSSelector::PseudoHost:
         case CSSSelector::PseudoAncestor:
             {
+                if (m_mode == SharingRules)
+                    return true;
                 // :host only matches a shadow host when :host is in a shadow tree of the shadow host.
                 if (!context.scope)
                     return false;
                 const ContainerNode* shadowHost = (context.behaviorAtBoundary & ScopeIsShadowHost) ? context.scope : (context.scope->isInShadowTree() ? context.scope->shadowHost() : 0);
                 if (!shadowHost || shadowHost != element)
                     return false;
                 ASSERT(element.shadow());
 
                 // For empty parameter case, i.e. just :host or :host().
                 if (!selector.selectorList()) // Use *'s specificity. So just 0.
@@ skipping 210 matching lines @@
     return element.focused() && isFrameFocused(element);
 }
 
 template
 SelectorChecker::Match SelectorChecker::match(const SelectorCheckingContext&, const DOMSiblingTraversalStrategy&, MatchResult*) const;
 
 template
 SelectorChecker::Match SelectorChecker::match(const SelectorCheckingContext&, const ShadowDOMSiblingTraversalStrategy&, MatchResult*) const;
 
 }