Rename :ancestor to :host-context.

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 854 matching lines @@
                     return true;
                 break;
             }
 
         case CSSSelector::PseudoUnresolved:
             if (element.isUnresolvedCustomElement())
                 return true;
             break;
 
         case CSSSelector::PseudoHost:
-        case CSSSelector::PseudoAncestor:
+        case CSSSelector::PseudoHostContext:
             {
                 // :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().
@@ skipping 211 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;
 
 }