webkitgtk-2.4.11webkitgtk-2.4.11

1 files changed, 184 insertions, 240 deletions

diff --git a/Source/WebCore/css/RuleSet.cpp b/Source/WebCore/css/RuleSet.cpp
index 0ebd5fc2d..c2752d9d1 100644
--- a/Source/WebCore/css/RuleSet.cpp
+++ b/Source/WebCore/css/RuleSet.cpp
@@ -2,7 +2,7 @@
  * 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) 2005-2014 Apple Inc. All rights reserved.
+ * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 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/)
@@ -30,18 +30,19 @@
 #include "RuleSet.h"
 
 #include "CSSFontSelector.h"
-#include "CSSKeyframesRule.h"
 #include "CSSSelector.h"
 #include "CSSSelectorList.h"
 #include "HTMLNames.h"
 #include "MediaQueryEvaluator.h"
 #include "SecurityOrigin.h"
 #include "SelectorChecker.h"
+#include "SelectorCheckerFastPath.h"
 #include "SelectorFilter.h"
 #include "StyleResolver.h"
 #include "StyleRule.h"
 #include "StyleRuleImport.h"
 #include "StyleSheetContents.h"
+#include "WebKitCSSKeyframesRule.h"
 
 #if ENABLE(VIDEO_TRACK)
 #include "TextTrackCue.h"
@@ -53,50 +54,33 @@ using namespace HTMLNames;
 
 // -----------------------------------------------------------------
 
-static inline MatchBasedOnRuleHash computeMatchBasedOnRuleHash(const CSSSelector& selector)
+static inline bool isSelectorMatchingHTMLBasedOnRuleHash(const CSSSelector* selector)
 {
-    if (selector.tagHistory())
-        return MatchBasedOnRuleHash::None;
-
-    if (selector.match() == CSSSelector::Tag) {
-        const QualifiedName& tagQualifiedName = selector.tagQName();
-        const AtomicString& selectorNamespace = tagQualifiedName.namespaceURI();
-        if (selectorNamespace == starAtom || selectorNamespace == xhtmlNamespaceURI) {
-            if (tagQualifiedName == anyQName())
-                return MatchBasedOnRuleHash::Universal;
-            return MatchBasedOnRuleHash::ClassC;
-        }
-        return MatchBasedOnRuleHash::None;
+    ASSERT(selector);
+    if (selector->m_match == CSSSelector::Tag) {
+        const AtomicString& selectorNamespace = selector->tagQName().namespaceURI();
+        if (selectorNamespace != starAtom && selectorNamespace != xhtmlNamespaceURI)
+            return false;
+        if (selector->relation() == CSSSelector::SubSelector)
+            return isSelectorMatchingHTMLBasedOnRuleHash(selector->tagHistory());
+        return true;
     }
-    if (SelectorChecker::isCommonPseudoClassSelector(&selector))
-        return MatchBasedOnRuleHash::ClassB;
-#if ENABLE(SHADOW_DOM)
-    if (selector.match() == CSSSelector::PseudoClass && selector.pseudoClassType() == CSSSelector::PseudoClassHost)
-        return MatchBasedOnRuleHash::ClassB;
-#endif
-    if (selector.match() == CSSSelector::Id)
-        return MatchBasedOnRuleHash::ClassA;
-    if (selector.match() == CSSSelector::Class)
-        return MatchBasedOnRuleHash::ClassB;
-    return MatchBasedOnRuleHash::None;
+    if (SelectorChecker::isCommonPseudoClassSelector(selector))
+        return true;
+    return selector->m_match == CSSSelector::Id || selector->m_match == CSSSelector::Class;
 }
 
-static bool selectorCanMatchPseudoElement(const CSSSelector& rootSelector)
+static inline bool selectorListContainsUncommonAttributeSelector(const CSSSelector* selector)
 {
-    const CSSSelector* selector = &rootSelector;
-    do {
-        if (selector->matchesPseudoElement())
-            return true;
-
-        if (const CSSSelectorList* selectorList = selector->selectorList()) {
-            for (const CSSSelector* subSelector = selectorList->first(); subSelector; subSelector = CSSSelectorList::next(subSelector)) {
-                if (selectorCanMatchPseudoElement(*subSelector))
-                    return true;
-            }
+    const CSSSelectorList* selectorList = selector->selectorList();
+    if (!selectorList)
+        return false;
+    for (const CSSSelector* selector = selectorList->first(); selector; selector = CSSSelectorList::next(selector)) {
+        for (const CSSSelector* component = selector; component; component = component->tagHistory()) {
+            if (component->isAttributeSelector())
+                return true;
         }
-
-        selector = selector->tagHistory();
-    } while (selector);
+    }
     return false;
 }
 
@@ -106,45 +90,36 @@ static inline bool isCommonAttributeSelectorAttribute(const QualifiedName& attri
     return attribute == typeAttr || attribute == readonlyAttr;
 }
 
-static bool containsUncommonAttributeSelector(const CSSSelector& rootSelector, bool matchesRightmostElement)
+static inline bool containsUncommonAttributeSelector(const CSSSelector* selector)
 {
-    const CSSSelector* selector = &rootSelector;
-    do {
-        if (selector->isAttributeSelector()) {
-            // FIXME: considering non-rightmost simple selectors is necessary because of the style sharing of cousins.
-            // It is a primitive solution which disable a lot of style sharing on pages that rely on attributes for styling.
-            // We should investigate better ways of doing this.
-            if (!isCommonAttributeSelectorAttribute(selector->attribute()) || !matchesRightmostElement)
-                return true;
-        }
-
-        if (const CSSSelectorList* selectorList = selector->selectorList()) {
-            for (const CSSSelector* subSelector = selectorList->first(); subSelector; subSelector = CSSSelectorList::next(subSelector)) {
-                if (containsUncommonAttributeSelector(*subSelector, matchesRightmostElement))
-                    return true;
-            }
+    for (; selector; selector = selector->tagHistory()) {
+        // Allow certain common attributes (used in the default style) in the selectors that match the current element.
+        if (selector->isAttributeSelector() && !isCommonAttributeSelectorAttribute(selector->attribute()))
+            return true;
+        if (selectorListContainsUncommonAttributeSelector(selector))
+            return true;
+        if (selector->relation() != CSSSelector::SubSelector) {
+            selector = selector->tagHistory();
+            break;
         }
+    }
 
-        if (selector->relation() != CSSSelector::SubSelector)
-            matchesRightmostElement = false;
-
-        selector = selector->tagHistory();
-    } while (selector);
+    for (; selector; selector = selector->tagHistory()) {
+        if (selector->isAttributeSelector())
+            return true;
+        if (selectorListContainsUncommonAttributeSelector(selector))
+            return true;
+    }
     return false;
 }
 
-static inline bool containsUncommonAttributeSelector(const CSSSelector& rootSelector)
-{
-    return containsUncommonAttributeSelector(rootSelector, true);
-}
-
 static inline PropertyWhitelistType determinePropertyWhitelistType(const AddRuleFlags addRuleFlags, const CSSSelector* selector)
 {
     if (addRuleFlags & RuleIsInRegionRule)
         return PropertyWhitelistRegion;
 #if ENABLE(VIDEO_TRACK)
     for (const CSSSelector* component = selector; component; component = component->tagHistory()) {
-        if (component->match() == CSSSelector::PseudoElement && (component->pseudoElementType() == CSSSelector::PseudoElementCue || component->value() == TextTrackCue::cueShadowPseudoId()))
+        if (component->pseudoType() == CSSSelector::PseudoCue || (component->m_match == CSSSelector::PseudoElement && component->value() == TextTrackCue::cueShadowPseudoId()))
             return PropertyWhitelistCue;
     }
 #else
@@ -156,145 +131,114 @@ static inline PropertyWhitelistType determinePropertyWhitelistType(const AddRule
 RuleData::RuleData(StyleRule* rule, unsigned selectorIndex, unsigned position, AddRuleFlags addRuleFlags)
     : m_rule(rule)
     , m_selectorIndex(selectorIndex)
-    , m_hasDocumentSecurityOrigin(addRuleFlags & RuleHasDocumentSecurityOrigin)
     , m_position(position)
-    , m_matchBasedOnRuleHash(static_cast<unsigned>(computeMatchBasedOnRuleHash(*selector())))
-    , m_canMatchPseudoElement(selectorCanMatchPseudoElement(*selector()))
-    , m_containsUncommonAttributeSelector(WebCore::containsUncommonAttributeSelector(*selector()))
+    , m_hasFastCheckableSelector((addRuleFlags & RuleCanUseFastCheckSelector) && SelectorCheckerFastPath::canUse(selector()))
+    , m_specificity(selector()->specificity())
+    , m_hasMultipartSelector(!!selector()->tagHistory())
+    , m_hasRightmostSelectorMatchingHTMLBasedOnRuleHash(isSelectorMatchingHTMLBasedOnRuleHash(selector()))
+    , m_containsUncommonAttributeSelector(WebCore::containsUncommonAttributeSelector(selector()))
     , m_linkMatchType(SelectorChecker::determineLinkMatchType(selector()))
+    , m_hasDocumentSecurityOrigin(addRuleFlags & RuleHasDocumentSecurityOrigin)
     , m_propertyWhitelistType(determinePropertyWhitelistType(addRuleFlags, selector()))
-#if ENABLE(CSS_SELECTOR_JIT) && CSS_SELECTOR_JIT_PROFILING
-    , m_compiledSelectorUseCount(0)
-#endif
 {
     ASSERT(m_position == position);
     ASSERT(m_selectorIndex == selectorIndex);
     SelectorFilter::collectIdentifierHashes(selector(), m_descendantSelectorIdentifierHashes, maximumIdentifierCount);
 }
 
-RuleSet::RuleSet()
-{
-}
-
-RuleSet::~RuleSet()
+static void collectFeaturesFromRuleData(RuleFeatureSet& features, const RuleData& ruleData)
 {
+    bool foundSiblingSelector = false;
+    for (const CSSSelector* selector = ruleData.selector(); selector; selector = selector->tagHistory()) {
+        features.collectFeaturesFromSelector(selector);
+        
+        if (const CSSSelectorList* selectorList = selector->selectorList()) {
+            for (const CSSSelector* subSelector = selectorList->first(); subSelector; subSelector = CSSSelectorList::next(subSelector)) {
+                if (!foundSiblingSelector && selector->isSiblingSelector())
+                    foundSiblingSelector = true;
+                features.collectFeaturesFromSelector(subSelector);
+            }
+        } else if (!foundSiblingSelector && selector->isSiblingSelector())
+            foundSiblingSelector = true;
+    }
+    if (foundSiblingSelector)
+        features.siblingRules.append(RuleFeature(ruleData.rule(), ruleData.selectorIndex(), ruleData.hasDocumentSecurityOrigin()));
+    if (ruleData.containsUncommonAttributeSelector())
+        features.uncommonAttributeRules.append(RuleFeature(ruleData.rule(), ruleData.selectorIndex(), ruleData.hasDocumentSecurityOrigin()));
 }
-
+    
 void RuleSet::addToRuleSet(AtomicStringImpl* key, AtomRuleMap& map, const RuleData& ruleData)
 {
     if (!key)
         return;
-    auto& rules = map.add(key, nullptr).iterator->value;
+    OwnPtr<Vector<RuleData>>& rules = map.add(key, nullptr).iterator->value;
     if (!rules)
-        rules = std::make_unique<RuleDataVector>();
+        rules = adoptPtr(new Vector<RuleData>);
     rules->append(ruleData);
 }
 
-static unsigned rulesCountForName(const RuleSet::AtomRuleMap& map, AtomicStringImpl* name)
-{
-    if (const auto* rules = map.get(name))
-        return rules->size();
-    return 0;
-}
-
-void RuleSet::addRule(StyleRule* rule, unsigned selectorIndex, AddRuleFlags addRuleFlags)
+bool RuleSet::findBestRuleSetAndAdd(const CSSSelector* component, RuleData& ruleData)
 {
-    RuleData ruleData(rule, selectorIndex, m_ruleCount++, addRuleFlags);
-    m_features.collectFeatures(ruleData);
-
-    unsigned classBucketSize = 0;
-    const CSSSelector* tagSelector = nullptr;
-    const CSSSelector* classSelector = nullptr;
-    const CSSSelector* linkSelector = nullptr;
-    const CSSSelector* focusSelector = nullptr;
-    const CSSSelector* selector = ruleData.selector();
-    do {
-        if (selector->match() == CSSSelector::Id) {
-            addToRuleSet(selector->value().impl(), m_idRules, ruleData);
-            return;
-        }
-
+    if (component->m_match == CSSSelector::Id) {
+        addToRuleSet(component->value().impl(), m_idRules, ruleData);
+        return true;
+    }
+    if (component->m_match == CSSSelector::Class) {
+        addToRuleSet(component->value().impl(), m_classRules, ruleData);
+        return true;
+    }
+    if (component->isCustomPseudoElement()) {
+        addToRuleSet(component->value().impl(), m_shadowPseudoElementRules, ruleData);
+        return true;
+    }
 #if ENABLE(VIDEO_TRACK)
-        if (selector->match() == CSSSelector::PseudoElement && selector->pseudoElementType() == CSSSelector::PseudoElementCue) {
-            m_cuePseudoRules.append(ruleData);
-            return;
-        }
+    if (component->pseudoType() == CSSSelector::PseudoCue) {
+        m_cuePseudoRules.append(ruleData);
+        return true;
+    }
 #endif
-
-        if (selector->isCustomPseudoElement()) {
-            // FIXME: Custom pseudo elements are handled by the shadow tree's selector filter. It doesn't know about the main DOM.
-            ruleData.disableSelectorFiltering();
-            addToRuleSet(selector->value().impl(), m_shadowPseudoElementRules, ruleData);
-            return;
-        }
-
-        if (selector->match() == CSSSelector::Class) {
-            AtomicStringImpl* className = selector->value().impl();
-            if (!classSelector) {
-                classSelector = selector;
-                classBucketSize = rulesCountForName(m_classRules, className);
-            } else if (classBucketSize) {
-                unsigned newClassBucketSize = rulesCountForName(m_classRules, className);
-                if (newClassBucketSize < classBucketSize) {
-                    classSelector = selector;
-                    classBucketSize = newClassBucketSize;
-                }
-            }
+    if (SelectorChecker::isCommonPseudoClassSelector(component)) {
+        switch (component->pseudoType()) {
+        case CSSSelector::PseudoLink:
+        case CSSSelector::PseudoVisited:
+        case CSSSelector::PseudoAnyLink:
+            m_linkPseudoClassRules.append(ruleData);
+            return true;
+        case CSSSelector::PseudoFocus:
+            m_focusPseudoClassRules.append(ruleData);
+            return true;
+        default:
+            ASSERT_NOT_REACHED();
+            return true;
         }
+    }
 
-        if (selector->match() == CSSSelector::Tag && selector->tagQName().localName() != starAtom)
-            tagSelector = selector;
-
-        if (SelectorChecker::isCommonPseudoClassSelector(selector)) {
-            switch (selector->pseudoClassType()) {
-            case CSSSelector::PseudoClassLink:
-            case CSSSelector::PseudoClassVisited:
-            case CSSSelector::PseudoClassAnyLink:
-            case CSSSelector::PseudoClassAnyLinkDeprecated:
-                linkSelector = selector;
-                break;
-            case CSSSelector::PseudoClassFocus:
-                focusSelector = selector;
-                break;
-            default:
-                ASSERT_NOT_REACHED();
+    if (component->m_match == CSSSelector::Tag) {
+        // If this is part of a subselector chain, recurse ahead to find a narrower set (ID/class/:pseudo)
+        if (component->relation() == CSSSelector::SubSelector) {
+            const CSSSelector* nextComponent = component->tagHistory();
+            if (nextComponent->m_match == CSSSelector::Class || nextComponent->m_match == CSSSelector::Id || SelectorChecker::isCommonPseudoClassSelector(nextComponent)) {
+                if (findBestRuleSetAndAdd(nextComponent, ruleData))
+                    return true;
             }
         }
-
-#if ENABLE(SHADOW_DOM)
-        if (selector->match() == CSSSelector::PseudoClass && selector->pseudoClassType() == CSSSelector::PseudoClassHost) {
-            m_hostPseudoClassRules.append(ruleData);
-            return;
+        if (component->tagQName().localName() != starAtom) {
+            addToRuleSet(component->tagQName().localName().impl(), m_tagRules, ruleData);
+            return true;
         }
-#endif
-        if (selector->relation() != CSSSelector::SubSelector)
-            break;
-        selector = selector->tagHistory();
-    } while (selector);
-
-    if (classSelector) {
-        addToRuleSet(classSelector->value().impl(), m_classRules, ruleData);
-        return;
-    }
-
-    if (linkSelector) {
-        m_linkPseudoClassRules.append(ruleData);
-        return;
     }
+    return false;
+}
 
-    if (focusSelector) {
-        m_focusPseudoClassRules.append(ruleData);
-        return;
-    }
+void RuleSet::addRule(StyleRule* rule, unsigned selectorIndex, AddRuleFlags addRuleFlags)
+{
+    RuleData ruleData(rule, selectorIndex, m_ruleCount++, addRuleFlags);
+    collectFeaturesFromRuleData(m_features, ruleData);
 
-    if (tagSelector) {
-        addToRuleSet(tagSelector->tagQName().localName().impl(), m_tagLocalNameRules, ruleData);
-        addToRuleSet(tagSelector->tagLowercaseLocalName().impl(), m_tagLowercaseLocalNameRules, ruleData);
-        return;
+    if (!findBestRuleSetAndAdd(ruleData.selector(), ruleData)) {
+        // If we didn't find a specialized map to stick it in, file under universal rules.
+        m_universalRules.append(ruleData);
     }
-
-    // If we didn't find a specialized map to stick it in, file under universal rules.
-    m_universalRules.append(ruleData);
 }
 
 void RuleSet::addPageRule(StyleRulePage* rule)
@@ -304,7 +248,7 @@ void RuleSet::addPageRule(StyleRulePage* rule)
 
 void RuleSet::addRegionRule(StyleRuleRegion* regionRule, bool hasDocumentSecurityOrigin)
 {
-    auto regionRuleSet = std::make_unique<RuleSet>();
+    OwnPtr<RuleSet> regionRuleSet = RuleSet::create();
     // The region rule set should take into account the position inside the parent rule set.
     // Otherwise, the rules inside region block might be incorrectly positioned before other similar rules from
     // the stylesheet that contains the region block.
@@ -314,63 +258,88 @@ void RuleSet::addRegionRule(StyleRuleRegion* regionRule, bool hasDocumentSecurit
     // FIXME: Should this add other types of rules? (i.e. use addChildRules() directly?)
     const Vector<RefPtr<StyleRuleBase>>& childRules = regionRule->childRules();
     AddRuleFlags addRuleFlags = hasDocumentSecurityOrigin ? RuleHasDocumentSecurityOrigin : RuleHasNoSpecialState;
-    addRuleFlags = static_cast<AddRuleFlags>(addRuleFlags | RuleIsInRegionRule);
-    for (auto& childRule : childRules) {
-        if (is<StyleRule>(*childRule))
-            regionRuleSet->addStyleRule(downcast<StyleRule>(childRule.get()), addRuleFlags);
+    addRuleFlags = static_cast<AddRuleFlags>(addRuleFlags | RuleCanUseFastCheckSelector | RuleIsInRegionRule);
+    for (unsigned i = 0; i < childRules.size(); ++i) {
+        StyleRuleBase* regionStylingRule = childRules[i].get();
+        if (regionStylingRule->isStyleRule())
+            regionRuleSet->addStyleRule(static_cast<StyleRule*>(regionStylingRule), addRuleFlags);
     }
     // Update the "global" rule count so that proper order is maintained
     m_ruleCount = regionRuleSet->m_ruleCount;
 
-    m_regionSelectorsAndRuleSets.append(RuleSetSelectorPair(regionRule->selectorList().first(), WTFMove(regionRuleSet)));
+    m_regionSelectorsAndRuleSets.append(RuleSetSelectorPair(regionRule->selectorList().first(), regionRuleSet.release()));
 }
 
-void RuleSet::addChildRules(const Vector<RefPtr<StyleRuleBase>>& rules, const MediaQueryEvaluator& medium, StyleResolver* resolver, bool hasDocumentSecurityOrigin, bool isInitiatingElementInUserAgentShadowTree, AddRuleFlags addRuleFlags)
+void RuleSet::addChildRules(const Vector<RefPtr<StyleRuleBase>>& rules, const MediaQueryEvaluator& medium, StyleResolver* resolver, const ContainerNode* scope, bool hasDocumentSecurityOrigin, AddRuleFlags addRuleFlags)
 {
-    for (auto& rule : rules) {
-        if (is<StyleRule>(*rule))
-            addStyleRule(downcast<StyleRule>(rule.get()), addRuleFlags);
-        else if (is<StyleRulePage>(*rule))
-            addPageRule(downcast<StyleRulePage>(rule.get()));
-        else if (is<StyleRuleMedia>(*rule)) {
-            auto& mediaRule = downcast<StyleRuleMedia>(*rule);
-            if ((!mediaRule.mediaQueries() || medium.eval(mediaRule.mediaQueries(), resolver)))
-                addChildRules(mediaRule.childRules(), medium, resolver, hasDocumentSecurityOrigin, isInitiatingElementInUserAgentShadowTree, addRuleFlags);
-        } else if (is<StyleRuleFontFace>(*rule) && resolver) {
+    for (unsigned i = 0; i < rules.size(); ++i) {
+        StyleRuleBase* rule = rules[i].get();
+
+        if (rule->isStyleRule()) {
+            StyleRule* styleRule = static_cast<StyleRule*>(rule);
+            addStyleRule(styleRule, addRuleFlags);
+        } else if (rule->isPageRule())
+            addPageRule(static_cast<StyleRulePage*>(rule));
+        else if (rule->isMediaRule()) {
+            StyleRuleMedia* mediaRule = static_cast<StyleRuleMedia*>(rule);
+            if ((!mediaRule->mediaQueries() || medium.eval(mediaRule->mediaQueries(), resolver)))
+                addChildRules(mediaRule->childRules(), medium, resolver, scope, hasDocumentSecurityOrigin, addRuleFlags);
+        } else if (rule->isFontFaceRule() && resolver) {
             // Add this font face to our set.
-            resolver->document().fontSelector().addFontFaceRule(downcast<StyleRuleFontFace>(*rule.get()), isInitiatingElementInUserAgentShadowTree);
+            // FIXME(BUG 72461): We don't add @font-face rules of scoped style sheets for the moment.
+            if (scope)
+                continue;
+            const StyleRuleFontFace* fontFaceRule = static_cast<StyleRuleFontFace*>(rule);
+            resolver->fontSelector()->addFontFaceRule(fontFaceRule);
             resolver->invalidateMatchedPropertiesCache();
-        } else if (is<StyleRuleKeyframes>(*rule) && resolver)
-            resolver->addKeyframeStyle(downcast<StyleRuleKeyframes>(rule.get()));
-        else if (is<StyleRuleSupports>(*rule) && downcast<StyleRuleSupports>(*rule).conditionIsSupported())
-            addChildRules(downcast<StyleRuleSupports>(*rule).childRules(), medium, resolver, hasDocumentSecurityOrigin, isInitiatingElementInUserAgentShadowTree, addRuleFlags);
+        } else if (rule->isKeyframesRule() && resolver) {
+            // FIXME (BUG 72462): We don't add @keyframe rules of scoped style sheets for the moment.
+            if (scope)
+                continue;
+            resolver->addKeyframeStyle(static_cast<StyleRuleKeyframes*>(rule));
+        }
 #if ENABLE(CSS_REGIONS)
-        else if (is<StyleRuleRegion>(*rule) && resolver) {
-            addRegionRule(downcast<StyleRuleRegion>(rule.get()), hasDocumentSecurityOrigin);
+        else if (rule->isRegionRule() && resolver) {
+            // FIXME (BUG 72472): We don't add @-webkit-region rules of scoped style sheets for the moment.
+            if (scope)
+                continue;
+            addRegionRule(static_cast<StyleRuleRegion*>(rule), hasDocumentSecurityOrigin);
         }
 #endif
+#if ENABLE(SHADOW_DOM)
+        else if (rule->isHostRule())
+            resolver->addHostRule(static_cast<StyleRuleHost*>(rule), hasDocumentSecurityOrigin, scope);
+#endif
 #if ENABLE(CSS_DEVICE_ADAPTATION)
-        else if (is<StyleRuleViewport>(*rule) && resolver) {
-            resolver->viewportStyleResolver()->addViewportRule(downcast<StyleRuleViewport>(rule.get()));
+        else if (rule->isViewportRule() && resolver) {
+            // @viewport should not be scoped.
+            if (scope)
+                continue;
+            resolver->viewportStyleResolver()->addViewportRule(static_cast<StyleRuleViewport*>(rule));
         }
 #endif
+#if ENABLE(CSS3_CONDITIONAL_RULES)
+        else if (rule->isSupportsRule() && static_cast<StyleRuleSupports*>(rule)->conditionIsSupported())
+            addChildRules(static_cast<StyleRuleSupports*>(rule)->childRules(), medium, resolver, scope, hasDocumentSecurityOrigin, addRuleFlags);
+#endif
     }
 }
 
-void RuleSet::addRulesFromSheet(StyleSheetContents& sheet, const MediaQueryEvaluator& medium, StyleResolver* resolver)
+void RuleSet::addRulesFromSheet(StyleSheetContents* sheet, const MediaQueryEvaluator& medium, StyleResolver* resolver, const ContainerNode* scope)
 {
-    for (auto& rule : sheet.importRules()) {
-        if (rule->styleSheet() && (!rule->mediaQueries() || medium.eval(rule->mediaQueries(), resolver)))
-            addRulesFromSheet(*rule->styleSheet(), medium, resolver);
+    ASSERT(sheet);
+
+    const Vector<RefPtr<StyleRuleImport>>& importRules = sheet->importRules();
+    for (unsigned i = 0; i < importRules.size(); ++i) {
+        StyleRuleImport* importRule = importRules[i].get();
+        if (importRule->styleSheet() && (!importRule->mediaQueries() || medium.eval(importRule->mediaQueries(), resolver)))
+            addRulesFromSheet(importRule->styleSheet(), medium, resolver, scope);
     }
 
-    bool hasDocumentSecurityOrigin = resolver && resolver->document().securityOrigin()->canRequest(sheet.baseURL());
-    AddRuleFlags addRuleFlags = static_cast<AddRuleFlags>((hasDocumentSecurityOrigin ? RuleHasDocumentSecurityOrigin : 0));
+    bool hasDocumentSecurityOrigin = resolver && resolver->document().securityOrigin()->canRequest(sheet->baseURL());
+    AddRuleFlags addRuleFlags = static_cast<AddRuleFlags>((hasDocumentSecurityOrigin ? RuleHasDocumentSecurityOrigin : 0) | (!scope ? RuleCanUseFastCheckSelector : 0));
 
-    // FIXME: Skip Content Security Policy check when stylesheet is in a user agent shadow tree.
-    // See <https://bugs.webkit.org/show_bug.cgi?id=146663>.
-    bool isInitiatingElementInUserAgentShadowTree = false;
-    addChildRules(sheet.childRules(), medium, resolver, hasDocumentSecurityOrigin, isInitiatingElementInUserAgentShadowTree, addRuleFlags);
+    addChildRules(sheet->childRules(), medium, resolver, scope, hasDocumentSecurityOrigin, addRuleFlags);
 
     if (m_autoShrinkToFitEnabled)
         shrinkToFit();
@@ -382,41 +351,18 @@ void RuleSet::addStyleRule(StyleRule* rule, AddRuleFlags addRuleFlags)
         addRule(rule, selectorIndex, addRuleFlags);
 }
 
-bool RuleSet::hasShadowPseudoElementRules() const
-{
-    if (!m_shadowPseudoElementRules.isEmpty())
-        return true;
-#if ENABLE(VIDEO_TRACK)
-    if (!m_cuePseudoRules.isEmpty())
-        return true;
-#endif
-    return false;
-}
-
-void RuleSet::copyShadowPseudoElementRulesFrom(const RuleSet& other)
-{
-    for (auto& keyValuePair : other.m_shadowPseudoElementRules)
-        m_shadowPseudoElementRules.add(keyValuePair.key, std::make_unique<RuleDataVector>(*keyValuePair.value));
-
-#if ENABLE(VIDEO_TRACK)
-    // FIXME: We probably shouldn't treat WebVTT as author stylable user agent shadow tree.
-    for (auto& cue : other.m_cuePseudoRules)
-        m_cuePseudoRules.append(cue);
-#endif
-}
-
 static inline void shrinkMapVectorsToFit(RuleSet::AtomRuleMap& map)
 {
-    for (auto& vector : map.values())
-        vector->shrinkToFit();
+    RuleSet::AtomRuleMap::iterator end = map.end();
+    for (RuleSet::AtomRuleMap::iterator it = map.begin(); it != end; ++it)
+        it->value->shrinkToFit();
 }
 
 void RuleSet::shrinkToFit()
 {
     shrinkMapVectorsToFit(m_idRules);
     shrinkMapVectorsToFit(m_classRules);
-    shrinkMapVectorsToFit(m_tagLocalNameRules);
-    shrinkMapVectorsToFit(m_tagLowercaseLocalNameRules);
+    shrinkMapVectorsToFit(m_tagRules);
     shrinkMapVectorsToFit(m_shadowPseudoElementRules);
     m_linkPseudoClassRules.shrinkToFit();
 #if ENABLE(VIDEO_TRACK)
@@ -425,8 +371,6 @@ void RuleSet::shrinkToFit()
     m_focusPseudoClassRules.shrinkToFit();
     m_universalRules.shrinkToFit();
     m_pageRules.shrinkToFit();
-    m_features.shrinkToFit();
-    m_regionSelectorsAndRuleSets.shrinkToFit();
 }
 
 } // namespace WebCore