Have SelectorQuery API take rootNode by reference

Source/core/css/ElementRuleCollector.cpp

Index: Source/core/css/ElementRuleCollector.cpp
diff --git a/Source/core/css/ElementRuleCollector.cpp b/Source/core/css/ElementRuleCollector.cpp
index 563860620a8c54b9e6d9d1a30f6985731f063224..d59f50d2c1bdea343800adcf00078765a1421af5 100644
--- a/Source/core/css/ElementRuleCollector.cpp
+++ b/Source/core/css/ElementRuleCollector.cpp
@@ -141,14 +141,14 @@ void ElementRuleCollector::collectMatchingRules(const MatchRequest& matchRequest
     ASSERT(matchRequest.ruleSet);
     ASSERT(m_context.element());
 
-    Element* element = m_context.element();
-    const AtomicString& pseudoId = element->shadowPseudoId();
+    Element& element = *m_context.element();
+    const AtomicString& pseudoId = element.shadowPseudoId();
     if (!pseudoId.isEmpty()) {
-        ASSERT(element->isStyledElement());
+        ASSERT(element.isStyledElement());
         collectMatchingRulesForList(matchRequest.ruleSet->shadowPseudoElementRules(pseudoId.impl()), behaviorAtBoundary, ignoreCascadeScope, cascadeOrder, matchRequest, ruleRange);
     }
 
-    if (element->isWebVTTElement())
+    if (element.isWebVTTElement())
         collectMatchingRulesForList(matchRequest.ruleSet->cuePseudoRules(), behaviorAtBoundary, cascadeScope, cascadeOrder, matchRequest, ruleRange);
     // Check whether other types of rules are applicable in the current tree scope. Criteria for this:
     // a) it's a UA rule
@@ -157,23 +157,23 @@ void ElementRuleCollector::collectMatchingRules(const MatchRequest& matchRequest
     // d) the rules comes from a scoped style sheet within an active shadow root whose host is the given element
     // e) the rules can cross boundaries
     // b)-e) is checked in rulesApplicableInCurrentTreeScope.
-    if (!m_matchingUARules && !rulesApplicableInCurrentTreeScope(element, matchRequest.scope, behaviorAtBoundary, matchRequest.elementApplyAuthorStyles))
+    if (!m_matchingUARules && !rulesApplicableInCurrentTreeScope(&element, matchRequest.scope, behaviorAtBoundary, matchRequest.elementApplyAuthorStyles))
         return;
 
     // We need to collect the rules for id, class, tag, and everything else into a buffer and
     // then sort the buffer.
-    if (element->hasID())
-        collectMatchingRulesForList(matchRequest.ruleSet->idRules(element->idForStyleResolution().impl()), behaviorAtBoundary, cascadeScope, cascadeOrder, matchRequest, ruleRange);
-    if (element->isStyledElement() && element->hasClass()) {
-        for (size_t i = 0; i < element->classNames().size(); ++i)
-            collectMatchingRulesForList(matchRequest.ruleSet->classRules(element->classNames()[i].impl()), behaviorAtBoundary, cascadeScope, cascadeOrder, matchRequest, ruleRange);
+    if (element.hasID())
+        collectMatchingRulesForList(matchRequest.ruleSet->idRules(element.idForStyleResolution().impl()), behaviorAtBoundary, cascadeScope, cascadeOrder, matchRequest, ruleRange);
+    if (element.isStyledElement() && element.hasClass()) {
+        for (size_t i = 0; i < element.classNames().size(); ++i)
+            collectMatchingRulesForList(matchRequest.ruleSet->classRules(element.classNames()[i].impl()), behaviorAtBoundary, cascadeScope, cascadeOrder, matchRequest, ruleRange);
     }
 
-    if (element->isLink())
+    if (element.isLink())
         collectMatchingRulesForList(matchRequest.ruleSet->linkPseudoClassRules(), behaviorAtBoundary, cascadeScope, cascadeOrder, matchRequest, ruleRange);
     if (SelectorChecker::matchesFocusPseudoClass(element))
         collectMatchingRulesForList(matchRequest.ruleSet->focusPseudoClassRules(), behaviorAtBoundary, cascadeScope, cascadeOrder, matchRequest, ruleRange);
-    collectMatchingRulesForList(matchRequest.ruleSet->tagRules(element->localName().impl()), behaviorAtBoundary, cascadeScope, cascadeOrder, matchRequest, ruleRange);
+    collectMatchingRulesForList(matchRequest.ruleSet->tagRules(element.localName().impl()), behaviorAtBoundary, cascadeScope, cascadeOrder, matchRequest, ruleRange);
     collectMatchingRulesForList(matchRequest.ruleSet->universalRules(), behaviorAtBoundary, cascadeScope, cascadeOrder, matchRequest, ruleRange);
 }
 
@@ -266,13 +266,14 @@ inline bool ElementRuleCollector::ruleMatches(const RuleData& ruleData, const Co
             return false;
         // We know a sufficiently simple single part selector matches simply because we found it from the rule hash.
         // This is limited to HTML only so we don't need to check the namespace.
+        ASSERT(m_context.element());
         if (ruleData.hasRightmostSelectorMatchingHTMLBasedOnRuleHash() && m_context.element()->isHTMLElement()) {
             if (!ruleData.hasMultipartSelector())
                 return true;
         }
-        if (ruleData.selector()->m_match == CSSSelector::Tag && !SelectorChecker::tagMatches(m_context.element(), ruleData.selector()->tagQName()))
+        if (ruleData.selector()->m_match == CSSSelector::Tag && !SelectorChecker::tagMatches(*m_context.element(), ruleData.selector()->tagQName()))
             return false;
-        SelectorCheckerFastPath selectorCheckerFastPath(ruleData.selector(), m_context.element());
+        SelectorCheckerFastPath selectorCheckerFastPath(ruleData.selector(), *m_context.element());
         if (!selectorCheckerFastPath.matchesRightmostAttributeSelector())
             return false;