Remove SelectorChecker::m_documentIsHTML

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 120 matching lines @@
     template<typename SiblingTraversalStrategy>
     Match matchForShadowDistributed(const Element*, const SiblingTraversalStrategy&, SelectorCheckingContext& nextContext, MatchResult* = 0) const;
     template<typename SiblingTraversalStrategy>
     Match matchForPseudoShadow(const ContainerNode*, const SelectorCheckingContext&, const SiblingTraversalStrategy&, MatchResult*) const;
 
     bool checkScrollbarPseudoClass(const SelectorCheckingContext&, Document*, const CSSSelector&) const;
 
     static bool isFrameFocused(const Element&);
 
     bool m_strictParsing;
-    bool m_documentIsHTML;
     Mode m_mode;
 };
 
 inline bool SelectorChecker::isCommonPseudoClassSelector(const CSSSelector& selector)
 {
     if (selector.match() != CSSSelector::PseudoClass)
         return false;
     CSSSelector::PseudoType pseudoType = selector.pseudoType();
     return pseudoType == CSSSelector::PseudoLink
         || pseudoType == CSSSelector::PseudoAnyLink
@@ skipping 24 matching lines @@
 }
 
 inline bool SelectorChecker::isHostInItsShadowTree(const Element& element, const ContainerNode* scope)
 {
     return scope && scope->isInShadowTree() && scope->shadowHost() == element;
 }
 
 }
 
 #endif