Implement proposed shadow tree cascade order.

Source/core/css/resolver/ScopedStyleResolver.cpp

Index: Source/core/css/resolver/ScopedStyleResolver.cpp
diff --git a/Source/core/css/resolver/ScopedStyleResolver.cpp b/Source/core/css/resolver/ScopedStyleResolver.cpp
index 72417408eb4f8990bd40edceca5e33a0ca0f3fa7..23150ca2aa99660be1cc8d54daa60e40b3fb6d7b 100644
--- a/Source/core/css/resolver/ScopedStyleResolver.cpp
+++ b/Source/core/css/resolver/ScopedStyleResolver.cpp
@@ -160,36 +160,44 @@ void ScopedStyleResolver::addKeyframeStyle(PassRefPtrWillBeRawPtr<StyleRuleKeyfr
     }
 }
 
-void ScopedStyleResolver::collectMatchingAuthorRules(ElementRuleCollector& collector, bool includeEmptyRules, CascadeOrder cascadeOrder)
+void ScopedStyleResolver::collectMatchingAuthorRules(ElementRuleCollector& collector, bool includeEmptyRules)
 {
     ASSERT(!collector.scopeContainsLastMatchedElement());
     collector.setScopeContainsLastMatchedElement(true);
     for (size_t i = 0; i < m_authorStyleSheets.size(); ++i) {
         ASSERT(m_authorStyleSheets[i]->ownerNode());
         MatchRequest matchRequest(&m_authorStyleSheets[i]->contents()->ruleSet(), includeEmptyRules, &m_scope->rootNode(), m_authorStyleSheets[i], i);
-        collector.collectMatchingRules(matchRequest, cascadeOrder);
+        collector.collectMatchingRules(matchRequest);
     }
     collector.setScopeContainsLastMatchedElement(false);
 }
 
-void ScopedStyleResolver::collectMatchingShadowHostRules(ElementRuleCollector& collector, bool includeEmptyRules, CascadeOrder cascadeOrder)
+void ScopedStyleResolver::collectMatchingShadowHostRules(ElementRuleCollector& collector, bool includeEmptyRules)
 {
     ASSERT(!collector.scopeContainsLastMatchedElement());
     collector.setScopeContainsLastMatchedElement(true);
     for (size_t i = 0; i < m_authorStyleSheets.size(); ++i) {
         ASSERT(m_authorStyleSheets[i]->ownerNode());
         MatchRequest matchRequest(&m_authorStyleSheets[i]->contents()->ruleSet(), includeEmptyRules, &m_scope->rootNode(), m_authorStyleSheets[i], i);
-        collector.collectMatchingShadowHostRules(matchRequest, cascadeOrder);
+        collector.collectMatchingShadowHostRules(matchRequest);
     }
     collector.setScopeContainsLastMatchedElement(false);
 }
 
-void ScopedStyleResolver::collectMatchingTreeBoundaryCrossingRules(ElementRuleCollector& collector, bool includeEmptyRules, CascadeOrder cascadeOrder)
+void ScopedStyleResolver::collectMatchingTreeBoundaryCrossingRules(ElementRuleCollector& collector, bool includeEmptyRules)
 {
+    if (!m_treeBoundaryCrossingRuleSet)
+        return;
+
+    ASSERT(!collector.scopeContainsLastMatchedElement());
+    collector.setScopeContainsLastMatchedElement(true);
+
     for (const auto& rules : *m_treeBoundaryCrossingRuleSet) {
         MatchRequest request(rules->m_ruleSet.get(), includeEmptyRules, &treeScope().rootNode(), rules->m_parentStyleSheet, rules->m_parentIndex);
-        collector.collectMatchingRules(request, cascadeOrder, true);
+        collector.collectMatchingRules(request, true);
     }
+
+    collector.setScopeContainsLastMatchedElement(false);
 }
 
 void ScopedStyleResolver::matchPageRules(PageRuleCollector& collector)