Scopeless matching of :host rules for style sharing.

third_party/WebKit/Source/core/css/ElementRuleCollector.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc.
  * All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 89 matching lines @@
 // Create one, ask what rules the ElementResolveContext matches
 // and then let it go out of scope.
 // FIXME: Currently it modifies the ComputedStyle but should not!
 class ElementRuleCollector {
   STACK_ALLOCATED();
   WTF_MAKE_NONCOPYABLE(ElementRuleCollector);
 
  public:
   ElementRuleCollector(const ElementResolveContext&,
                        const SelectorFilter&,
-                       ComputedStyle* = 0);
+                       ComputedStyle* = nullptr);
   ~ElementRuleCollector();
 
   void SetMode(SelectorChecker::Mode mode) { mode_ = mode; }
   void SetPseudoStyleRequest(const PseudoStyleRequest& request) {
     pseudo_style_request_ = request;
   }
   void SetSameOriginOnly(bool f) { same_origin_only_ = f; }
 
   void SetMatchingUARules(bool matching_ua_rules) {
     matching_ua_rules_ = matching_ua_rules;
@@ skipping 61 matching lines @@
 
   // Output.
   Member<StaticCSSRuleList> css_rule_list_;
   Member<StyleRuleList> style_rule_list_;
   MatchResult result_;
 };
 
 }  // namespace blink
 
 #endif  // ElementRuleCollector_h