Make SelectorChecker a const operation over element.

sky/engine/core/css/SelectorChecker.h

 /*
  * 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 23 matching lines @@
 namespace blink {
 
 class CSSSelector;
 class ContainerNode;
 class Element;
 class RenderStyle;
 
 class SelectorChecker {
     WTF_MAKE_NONCOPYABLE(SelectorChecker);
 public:
-    enum Mode { ResolvingStyle = 0, QueryingRules, SharingRules };
-    explicit SelectorChecker(Document&, Mode);
+    explicit SelectorChecker();
 
     struct SelectorCheckingContext {
         STACK_ALLOCATED();
     public:
         // Initial selector constructor
-        SelectorCheckingContext(const CSSSelector& selector, Element* element)
+        SelectorCheckingContext(const CSSSelector& selector, const Element* element)
             : selector(&selector)
             , element(element)
             , scope(nullptr)
-            , elementStyle(0)
         {
         }
 
         const CSSSelector* selector;
-        RawPtr<Element> element;
+        const Element* element;
         RawPtr<const ContainerNode> scope;
-        RenderStyle* elementStyle;
     };
 
-    bool match(const SelectorCheckingContext&) const;
+    bool match(const SelectorCheckingContext&);
+
+    bool matchedAttributeSelector() const { return m_matchedAttributeSelector; }
+    bool matchedFocusSelector() const { return m_matchedFocusSelector; }
+    bool matchedHoverSelector() const { return m_matchedHoverSelector; }
+    bool matchedActiveSelector() const { return m_matchedActiveSelector; }
 
     static bool tagMatches(const Element&, const QualifiedName&);
     static bool isHostInItsShadowTree(const Element&, const ContainerNode* scope);
 
 private:
-    bool checkPseudoClass(const SelectorCheckingContext&) const;
-    bool checkOne(const SelectorCheckingContext&) const;
-
-    Mode mode() const { return m_mode; }
+    bool checkPseudoClass(const SelectorCheckingContext&);
+    bool checkOne(const SelectorCheckingContext&);
 
     static bool checkExactAttribute(const Element&, const QualifiedName& selectorAttributeName, const StringImpl* value);
     static bool matchesFocusPseudoClass(const Element&);
 
-    Mode m_mode;
+    bool m_matchedAttributeSelector;
+    bool m_matchedFocusSelector;
+    bool m_matchedHoverSelector;
+    bool m_matchedActiveSelector;
 };
 
 inline bool SelectorChecker::tagMatches(const Element& element, const QualifiedName& tagQName)
 {
     const AtomicString& localName = tagQName.localName();
     return localName == starAtom || localName == element.localName();
 }
 
 inline bool SelectorChecker::checkExactAttribute(const Element& element, const QualifiedName& selectorAttributeName, const StringImpl* value)
 {
     AttributeCollection attributes = element.attributesWithoutUpdate();
     AttributeCollection::iterator end = attributes.end();
     for (AttributeCollection::iterator it = attributes.begin(); it != end; ++it) {
         if (it->matches(selectorAttributeName) && (!value || it->value().impl() == value))
             return true;
     }
     return false;
 }
 
 inline bool SelectorChecker::isHostInItsShadowTree(const Element& element, const ContainerNode* scope)
 {
     return scope && scope->isInShadowTree() && scope->shadowHost() == element;
 }
 
 }
 
 #endif  // SKY_ENGINE_CORE_CSS_SELECTORCHECKER_H_