Pass around CSSSelector by reference instead of pointer

Source/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 48 matching lines @@
         ScopeIsShadowHostInPseudoHostParameter = ScopeIsShadowHost | TreatShadowHostAsNormalScope
     };
 
     enum MatchingTagType {
         MatchingElement = 0,
         MatchingHostInItsShadowTree
     };
 
     struct SelectorCheckingContext {
         // Initial selector constructor
-        SelectorCheckingContext(const CSSSelector* selector, Element* element, VisitedMatchType visitedMatchType)
-            : selector(selector)
+        SelectorCheckingContext(const CSSSelector& selector, Element* element, VisitedMatchType visitedMatchType)
+            : selector(&selector)
             , element(element)
             , scope(0)
             , visitedMatchType(visitedMatchType)
             , pseudoId(NOPSEUDO)
             , elementStyle(0)
             , scrollbar(0)
             , scrollbarPart(NoPart)
             , isSubSelector(false)
             , hasScrollbarPseudo(false)
             , hasSelectionPseudo(false)
@@ skipping 27 matching lines @@
     Match match(const SelectorCheckingContext&, const SiblingTraversalStrategy&, MatchResult* = 0) const;
 
     template<typename SiblingTraversalStrategy>
     bool checkOne(const SelectorCheckingContext&, const SiblingTraversalStrategy&, unsigned* specificity = 0) const;
 
     bool strictParsing() const { return m_strictParsing; }
 
     Mode mode() const { return m_mode; }
 
     static bool tagMatches(const Element&, const QualifiedName&, MatchingTagType = MatchingElement);
-    static bool isCommonPseudoClassSelector(const CSSSelector*);
+    static bool isCommonPseudoClassSelector(const CSSSelector&);
     static bool matchesFocusPseudoClass(const Element&);
     static bool checkExactAttribute(const Element&, const QualifiedName& selectorAttributeName, const StringImpl* value);
 
     enum LinkMatchMask { MatchLink = 1, MatchVisited = 2, MatchAll = MatchLink | MatchVisited };
-    static unsigned determineLinkMatchType(const CSSSelector*);
+    static unsigned determineLinkMatchType(const CSSSelector&);
 
     static bool isHostInItsShadowTree(const Element&, BehaviorAtBoundary, const ContainerNode* scope);
 
 private:
     template<typename SiblingTraversalStrategy>
     Match matchForSubSelector(const SelectorCheckingContext&, const SiblingTraversalStrategy&, MatchResult*) const;
     template<typename SiblingTraversalStrategy>
     Match matchForRelation(const SelectorCheckingContext&, const SiblingTraversalStrategy&, MatchResult*) const;
     template<typename SiblingTraversalStrategy>
     Match matchForShadowDistributed(const Element*, const SiblingTraversalStrategy&, SelectorCheckingContext& nextContext, MatchResult* = 0) const;
 
-    bool checkScrollbarPseudoClass(const SelectorCheckingContext&, Document*, const CSSSelector*) const;
+    bool checkScrollbarPseudoClass(const SelectorCheckingContext&, Document*, const CSSSelector&) const;
     Element* parentElement(const SelectorCheckingContext&, bool allowToCrossBoundary = false) const;
     bool scopeContainsLastMatchedElement(const SelectorCheckingContext&) const;
 
     static bool isFrameFocused(const Element&);
 
     bool m_strictParsing;
     bool m_documentIsHTML;
     Mode m_mode;
 };
 
-inline bool SelectorChecker::isCommonPseudoClassSelector(const CSSSelector* selector)
+inline bool SelectorChecker::isCommonPseudoClassSelector(const CSSSelector& selector)
 {
-    if (selector->m_match != CSSSelector::PseudoClass)
+    if (selector.m_match != CSSSelector::PseudoClass)
         return false;
-    CSSSelector::PseudoType pseudoType = selector->pseudoType();
+    CSSSelector::PseudoType pseudoType = selector.pseudoType();
     return pseudoType == CSSSelector::PseudoLink
         || pseudoType == CSSSelector::PseudoAnyLink
         || pseudoType == CSSSelector::PseudoVisited
         || pseudoType == CSSSelector::PseudoFocus;
 }
 
 inline bool SelectorChecker::tagMatches(const Element& element, const QualifiedName& tagQName, MatchingTagType matchingTagType)
 {
     if (tagQName == anyQName())
         return true;
@@ skipping 18 matching lines @@
 }
 
 inline bool SelectorChecker::isHostInItsShadowTree(const Element& element, BehaviorAtBoundary behaviorAtBoundary, const ContainerNode* scope)
 {
     return (behaviorAtBoundary & (ScopeIsShadowHost | TreatShadowHostAsNormalScope)) == ScopeIsShadowHost && scope == element;
 }
 
 }
 
 #endif