Implement proposed shadow tree cascade order.

Source/core/css/resolver/StyleResolver.h

Index: Source/core/css/resolver/StyleResolver.h
diff --git a/Source/core/css/resolver/StyleResolver.h b/Source/core/css/resolver/StyleResolver.h
index 6872b6a6e57ac81e94c8806fc7c2f6b887b9320e..387ec2b83fd5ed1352cc9da23ce5dbf795efa4cf 100644
--- a/Source/core/css/resolver/StyleResolver.h
+++ b/Source/core/css/resolver/StyleResolver.h
@@ -30,12 +30,12 @@
 #include "core/css/RuleSet.h"
 #include "core/css/SelectorChecker.h"
 #include "core/css/SelectorFilter.h"
-#include "core/css/TreeBoundaryCrossingRules.h"
 #include "core/css/resolver/CSSPropertyPriority.h"
 #include "core/css/resolver/MatchedPropertiesCache.h"
 #include "core/css/resolver/StyleBuilder.h"
 #include "core/css/resolver/StyleResolverStats.h"
 #include "core/css/resolver/StyleResourceLoader.h"
+#include "core/dom/DocumentOrderedList.h"
 #include "core/style/AuthorStyleInfo.h"
 #include "core/style/CachedUAStyle.h"
 #include "platform/heap/Handle.h"
@@ -201,7 +201,10 @@ private:
     void collectPseudoRulesForElement(Element*, ElementRuleCollector&, PseudoId, unsigned rulesToInclude);
     void matchRuleSet(ElementRuleCollector&, RuleSet*);
     void matchUARules(ElementRuleCollector&);
-    void matchAuthorRules(Element*, ElementRuleCollector&, bool includeEmptyRules);
+    void matchAuthorRules(const Element&, ElementRuleCollector&, bool includeEmptyRules);
+    void matchHostRules(const Element&, ElementRuleCollector&, bool includeEmptyRules);
+    void matchElementScopeRules(ScopedStyleResolver*, ElementRuleCollector&, bool includeEmptyRules);
+    void matchScopedRules(const Element&, ElementRuleCollector&, bool includeEmptyRules);
     void matchAllRules(StyleResolverState&, ElementRuleCollector&, bool includeSMILProperties);
     void collectFeatures();
     void resetRuleFeatures();
@@ -245,7 +248,7 @@ private:
     OwnPtrWillBeMember<RuleSet> m_siblingRuleSet;
     OwnPtrWillBeMember<RuleSet> m_uncommonAttributeRuleSet;
     OwnPtrWillBeMember<RuleSet> m_watchedSelectorsRules;
-    TreeBoundaryCrossingRules m_treeBoundaryCrossingRules;
+    DocumentOrderedList m_treeBoundaryCrossingScopes;
 
     bool m_needCollectFeatures;
     bool m_printMediaType;