Current work-in-progress crbug.com/567021

third_party/WebKit/Source/core/dom/StyleEngine.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All
  * rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
@@ skipping 122 matching lines @@
     return documentStyleSheetCollection().styleSheetsForStyleSheetList();
 
   return ensureStyleSheetCollectionFor(treeScope)
       ->styleSheetsForStyleSheetList();
 }
 
 void StyleEngine::injectAuthorSheet(StyleSheetContents* authorSheet) {
   m_injectedAuthorStyleSheets.append(TraceWrapperMember<CSSStyleSheet>(
       this, CSSStyleSheet::create(authorSheet, *m_document)));
   markDocumentDirty();
-  resolverChanged(AnalyzedStyleUpdate);
 }
 
 CSSStyleSheet& StyleEngine::ensureInspectorStyleSheet() {
   if (m_inspectorStyleSheet)
     return *m_inspectorStyleSheet;
 
   StyleSheetContents* contents =
       StyleSheetContents::create(CSSParserContext(*m_document, nullptr));
   m_inspectorStyleSheet = CSSStyleSheet::create(contents, *m_document);
   markDocumentDirty();
-  resolverChanged(AnalyzedStyleUpdate);
+  // TODO(rune@opera.com): Making the active stylesheets up-to-date here is
+  // required by some inspector tests, at least. I theory this should not be
+  // necessary. Need to investigate to figure out if/why.
+  updateActiveStyle();
   return *m_inspectorStyleSheet;
 }
 
 void StyleEngine::addPendingSheet(StyleEngineContext& context) {
   m_pendingScriptBlockingStylesheets++;
 
   context.addingPendingSheet(document());
   if (context.addedPendingSheetBeforeBody())
     m_pendingRenderBlockingStylesheets++;
 }
@@ skipping 13 matching lines @@
   // sync.
   DCHECK_GT(m_pendingScriptBlockingStylesheets, 0);
 
   m_pendingScriptBlockingStylesheets--;
   if (m_pendingScriptBlockingStylesheets)
     return;
 
   document().didRemoveAllPendingStylesheet();
 }
 
-void StyleEngine::setNeedsActiveStyleUpdate(
-    StyleSheet* sheet,
-    StyleResolverUpdateMode updateMode) {
-  // resolverChanged() is called for inactive non-master documents because
-  // import documents are inactive documents. resolverChanged() for imports
-  // will call resolverChanged() for the master document and update the active
-  // stylesheets including the ones from the import.
+void StyleEngine::setNeedsActiveStyleUpdate(TreeScope& treeScope) {
   if (!document().isActive() && isMaster())
     return;
-
-  if (sheet && document().isActive()) {
-    Node* node = sheet->ownerNode();
-    if (node && node->isConnected())
-      markTreeScopeDirty(node->treeScope());
-  }
-
-  resolverChanged(updateMode);
+  markTreeScopeDirty(treeScope);
 }
 
 void StyleEngine::addStyleSheetCandidateNode(Node& node) {
   if (!node.isConnected() || document().isDetached())
     return;
 
   DCHECK(!isXSLStyleSheet(node));
   TreeScope& treeScope = node.treeScope();
   TreeScopeStyleSheetCollection* collection =
       ensureStyleSheetCollectionFor(treeScope);
@@ skipping 18 matching lines @@
   // After detaching document, collection could be null. In the case,
   // we should not update anything. Instead, just return.
   if (!collection)
     return;
   collection->removeStyleSheetCandidateNode(node);
 
   markTreeScopeDirty(treeScope);
 }
 
 void StyleEngine::modifiedStyleSheetCandidateNode(Node& node) {
-  if (!node.isConnected())
-    return;
+  if (node.isConnected())
+    markTreeScopeDirty(node.treeScope());
+}
 
-  markTreeScopeDirty(node.treeScope());
-  resolverChanged(AnalyzedStyleUpdate);
+void StyleEngine::mediaQueriesChangedInScope(TreeScope& treeScope) {
+  if (ScopedStyleResolver* resolver = treeScope.scopedStyleResolver()) {
+    resolver->setNeedsAppendAllSheets();
+    setNeedsActiveStyleUpdate(treeScope);
+  }
 }
 
 void StyleEngine::watchedSelectorsChanged() {
   m_globalRuleSet.initWatchedSelectorsRuleSet(document());
   // TODO(rune@opera.com): Should be able to use RuleSetInvalidation here.
   document().setNeedsStyleRecalc(SubtreeStyleChange,
                                  StyleChangeReasonForTracing::create(
                                      StyleChangeReason::DeclarativeContent));
 }
 
 bool StyleEngine::shouldUpdateDocumentStyleSheetCollection() const {
   return m_allTreeScopesDirty || m_documentScopeDirty;
 }
 
 bool StyleEngine::shouldUpdateShadowTreeStyleSheetCollection() const {
   return m_allTreeScopesDirty || !m_dirtyTreeScopes.isEmpty();
 }
 
 void StyleEngine::mediaQueryAffectingValueChanged(
     UnorderedTreeScopeSet& treeScopes) {
   for (TreeScope* treeScope : treeScopes) {
     DCHECK(treeScope != m_document);
     ShadowTreeStyleSheetCollection* collection =
         toShadowTreeStyleSheetCollection(styleSheetCollectionFor(*treeScope));
     DCHECK(collection);
-    collection->clearMediaQueryRuleSetStyleSheets();
+    if (collection->mediaQueryAffectingValueChanged())
+      setNeedsActiveStyleUpdate(*treeScope);
   }
 }
 
 void StyleEngine::mediaQueryAffectingValueChanged() {
-  resolverChanged(FullStyleUpdate);
-  documentStyleSheetCollection().clearMediaQueryRuleSetStyleSheets();
+  if (documentStyleSheetCollection().mediaQueryAffectingValueChanged())
+    setNeedsActiveStyleUpdate(document());
   mediaQueryAffectingValueChanged(m_activeTreeScopes);
   if (m_resolver)
     m_resolver->updateMediaType();
 }
 
 void StyleEngine::updateStyleSheetsInImport(
     DocumentStyleSheetCollector& parentCollector) {
   DCHECK(!isMaster());
   HeapVector<Member<StyleSheet>> sheetsForList;
   ImportedDocumentStyleSheetCollector subcollector(parentCollector,
                                                    sheetsForList);
-  documentStyleSheetCollection().collectStyleSheets(*this, subcollector);
+  documentStyleSheetCollection().collectStyleSheets(subcollector);
   documentStyleSheetCollection().swapSheetsForSheetList(sheetsForList);
 }
 
 void StyleEngine::updateActiveStyleSheetsInShadow(
-    StyleResolverUpdateMode updateMode,
     TreeScope* treeScope,
     UnorderedTreeScopeSet& treeScopesRemoved) {
   DCHECK_NE(treeScope, m_document);
   ShadowTreeStyleSheetCollection* collection =
       toShadowTreeStyleSheetCollection(styleSheetCollectionFor(*treeScope));
   DCHECK(collection);
-  collection->updateActiveStyleSheets(*this, updateMode);
+  collection->updateActiveStyleSheets();
   if (!collection->hasStyleSheetCandidateNodes()) {
     treeScopesRemoved.add(treeScope);
     // When removing TreeScope from ActiveTreeScopes,
     // its resolver should be destroyed by invoking resetAuthorStyle.
     DCHECK(!treeScope->scopedStyleResolver());
   }
 }
 
-void StyleEngine::updateActiveStyleSheets(StyleResolverUpdateMode updateMode) {
+void StyleEngine::updateActiveStyleSheets() {
+  if (!needsActiveStyleSheetUpdate())
+    return;
+
   DCHECK(isMaster());
   DCHECK(!document().inStyleRecalc());
-
-  if (!document().isActive())
-    return;
+  DCHECK(document().isActive());
 
   TRACE_EVENT0("blink,blink_style", "StyleEngine::updateActiveStyleSheets");
 
   if (shouldUpdateDocumentStyleSheetCollection())
-    documentStyleSheetCollection().updateActiveStyleSheets(*this, updateMode);
+    documentStyleSheetCollection().updateActiveStyleSheets();
 
   if (shouldUpdateShadowTreeStyleSheetCollection()) {
     UnorderedTreeScopeSet treeScopesRemoved;
 
     if (m_allTreeScopesDirty) {
       for (TreeScope* treeScope : m_activeTreeScopes)
-        updateActiveStyleSheetsInShadow(updateMode, treeScope,
-                                        treeScopesRemoved);
+        updateActiveStyleSheetsInShadow(treeScope, treeScopesRemoved);
     } else {
       for (TreeScope* treeScope : m_dirtyTreeScopes)
-        updateActiveStyleSheetsInShadow(updateMode, treeScope,
-                                        treeScopesRemoved);
+        updateActiveStyleSheetsInShadow(treeScope, treeScopesRemoved);
     }
     for (TreeScope* treeScope : treeScopesRemoved)
       m_activeTreeScopes.remove(treeScope);
   }
 
   InspectorInstrumentation::activeStyleSheetsUpdated(m_document);
 
   m_dirtyTreeScopes.clear();
   m_documentScopeDirty = false;
   m_allTreeScopesDirty = false;
 }
 
-void StyleEngine::updateActiveStyleSheets() {
-  // TODO(rune@opera.com): collect ActiveStyleSheets here.
-}
-
 void StyleEngine::updateViewport() {
   if (m_viewportResolver)
     m_viewportResolver->updateViewport(documentStyleSheetCollection());
 }
 
 bool StyleEngine::needsActiveStyleUpdate() const {
-  return m_viewportResolver && m_viewportResolver->needsUpdate();
+  return (m_viewportResolver && m_viewportResolver->needsUpdate()) ||
+         needsActiveStyleSheetUpdate() || m_globalRuleSet.isDirty();
 }
 
 void StyleEngine::updateActiveStyle() {
+  DCHECK(document().isActive());
   updateViewport();
   updateActiveStyleSheets();
   m_globalRuleSet.update(document());
 }
 
-const HeapVector<Member<CSSStyleSheet>>
-StyleEngine::activeStyleSheetsForInspector() const {
+const ActiveStyleSheetVector StyleEngine::activeStyleSheetsForInspector() {
+  if (document().isActive())
+    updateActiveStyle();
+
   if (m_activeTreeScopes.isEmpty())
     return documentStyleSheetCollection().activeAuthorStyleSheets();
 
-  HeapVector<Member<CSSStyleSheet>> activeStyleSheets;
+  ActiveStyleSheetVector activeStyleSheets;
 
   activeStyleSheets.appendVector(
       documentStyleSheetCollection().activeAuthorStyleSheets());
   for (TreeScope* treeScope : m_activeTreeScopes) {
     if (TreeScopeStyleSheetCollection* collection =
             m_styleSheetCollectionMap.get(treeScope))
       activeStyleSheets.appendVector(collection->activeAuthorStyleSheets());
   }
 
   // FIXME: Inspector needs a vector which has all active stylesheets.
   // However, creating such a large vector might cause performance regression.
   // Need to implement some smarter solution.
   return activeStyleSheets;
 }
 
 void StyleEngine::shadowRootRemovedFromDocument(ShadowRoot* shadowRoot) {
-  if (StyleResolver* styleResolver = resolver()) {
-    if (TreeScopeStyleSheetCollection* collection =
-            styleSheetCollectionFor(*shadowRoot))
-      styleResolver->removePendingAuthorStyleSheets(
-          collection->activeAuthorStyleSheets());
-  }
   m_styleSheetCollectionMap.remove(shadowRoot);
   m_activeTreeScopes.remove(shadowRoot);
   m_dirtyTreeScopes.remove(shadowRoot);
   resetAuthorStyle(*shadowRoot);
 }
 
 void StyleEngine::addTreeBoundaryCrossingScope(const TreeScope& treeScope) {
   m_treeBoundaryCrossingScopes.add(&treeScope.rootNode());
 }
 
 void StyleEngine::resetAuthorStyle(TreeScope& treeScope) {
   m_treeBoundaryCrossingScopes.remove(&treeScope.rootNode());
 
   ScopedStyleResolver* scopedResolver = treeScope.scopedStyleResolver();
   if (!scopedResolver)
     return;
 
   m_globalRuleSet.markDirty();
   if (treeScope.rootNode().isDocumentNode()) {
     scopedResolver->resetAuthorStyle();
     return;
   }
 
   treeScope.clearScopedStyleResolver();
 }
 
-void StyleEngine::finishAppendAuthorStyleSheets() {
-  m_globalRuleSet.markDirty();
-  m_globalRuleSet.update(document());
-
-  if (!document().layoutViewItem().isNull() &&
-      document().layoutViewItem().style())
-    document().layoutViewItem().style()->font().update(fontSelector());
-}
-
-void StyleEngine::appendActiveAuthorStyleSheets() {
-  DCHECK(isMaster());
-
-  m_resolver->appendAuthorStyleSheets(
-      documentStyleSheetCollection().activeAuthorStyleSheets());
-  for (TreeScope* treeScope : m_activeTreeScopes) {
-    if (TreeScopeStyleSheetCollection* collection =
-            m_styleSheetCollectionMap.get(treeScope))
-      m_resolver->appendAuthorStyleSheets(
-          collection->activeAuthorStyleSheets());
-  }
-}
-
 void StyleEngine::setRuleUsageTracker(StyleRuleUsageTracker* tracker) {
   m_tracker = tracker;
 
   if (m_resolver)
     m_resolver->setRuleUsageTracker(m_tracker);
 }
 
 RuleSet* StyleEngine::ruleSetForSheet(CSSStyleSheet& sheet) {
   if (!sheet.matchesMediaQueries(ensureMediaQueryEvaluator()))
     return nullptr;
 
   AddRuleFlags addRuleFlags = RuleHasNoSpecialState;
   if (m_document->getSecurityOrigin()->canRequest(sheet.baseURL()))
     addRuleFlags = RuleHasDocumentSecurityOrigin;
   return &sheet.contents()->ensureRuleSet(*m_mediaQueryEvaluator, addRuleFlags);
 }
 
 void StyleEngine::createResolver() {
   m_resolver = StyleResolver::create(*m_document);
-
   m_resolver->setRuleUsageTracker(m_tracker);
-
-  // A scoped style resolver for document will be created during
-  // appendActiveAuthorStyleSheets if needed.
-  appendActiveAuthorStyleSheets();
-  finishAppendAuthorStyleSheets();
 }
 
 void StyleEngine::clearResolver() {
   DCHECK(!document().inStyleRecalc());
   DCHECK(isMaster() || !m_resolver);
 
   document().clearScopedStyleResolver();
   // TODO(rune@opera.com): The clearing of all shadow tree scoped style
   // resolvers below should not be necessary. It was introduced to fix a crash
   // bug (https://crbug.com/447976) when clearResolver is called from didDetach
@@ skipping 12 matching lines @@
   m_treeBoundaryCrossingScopes.clear();
 
   if (m_resolver) {
     TRACE_EVENT1("blink", "StyleEngine::clearResolver", "frame",
                  document().frame());
     m_resolver->dispose();
     m_resolver.clear();
   }
 }
 
-void StyleEngine::clearMasterResolver() {
-  if (Document* master = this->master())
-    master->styleEngine().clearResolver();
-}
-
 void StyleEngine::didDetach() {
   clearResolver();
   m_viewportResolver = nullptr;
   m_mediaQueryEvaluator = nullptr;
 }
 
-bool StyleEngine::shouldClearResolver() const {
-  return !m_didCalculateResolver && !haveScriptBlockingStylesheetsLoaded();
-}
-
-void StyleEngine::resolverChanged(StyleResolverUpdateMode mode) {
-  if (!isMaster()) {
-    if (Document* master = this->master())
-      master->styleEngine().resolverChanged(mode);
-    return;
-  }
-
-  // Don't bother updating, since we haven't loaded all our style info yet
-  // and haven't calculated the style selector for the first time.
-  if (!document().isActive() || shouldClearResolver()) {
-    clearResolver();
-    return;
-  }
-
-  if (mode == FullStyleUpdate)
-    markAllTreeScopesDirty();
-  m_didCalculateResolver = true;
-  updateActiveStyleSheets(mode);
-}
-
 void StyleEngine::clearFontCache() {
   if (m_fontSelector)
     m_fontSelector->fontFaceCache()->clearCSSConnected();
   if (m_resolver)
     m_resolver->invalidateMatchedPropertiesCache();
 }
 
 void StyleEngine::updateGenericFontFamilySettings() {
   // FIXME: we should not update generic font family settings when
   // document is inactive.
@@ skipping 21 matching lines @@
 }
 
 void StyleEngine::markTreeScopeDirty(TreeScope& scope) {
   if (scope == m_document) {
     markDocumentDirty();
     return;
   }
 
   DCHECK(m_styleSheetCollectionMap.contains(&scope));
   m_dirtyTreeScopes.add(&scope);
+  document().scheduleLayoutTreeUpdateIfNeeded();
 }
 
 void StyleEngine::markDocumentDirty() {
   m_documentScopeDirty = true;
   if (RuntimeEnabledFeatures::cssViewportEnabled())
     viewportRulesChanged();
   if (document().importLoader())
     document().importsController()->master()->styleEngine().markDocumentDirty();
+  else
+    document().scheduleLayoutTreeUpdateIfNeeded();
 }
 
 CSSStyleSheet* StyleEngine::createSheet(Element& element,
                                         const String& text,
                                         TextPosition startPosition,
                                         StyleEngineContext& context) {
   DCHECK(element.document() == document());
   CSSStyleSheet* styleSheet = nullptr;
 
   addPendingSheet(context);
@@ skipping 14 matching lines @@
     DCHECK(contents);
     DCHECK(contents->isCacheableForStyleElement());
     DCHECK(contents->hasSingleOwnerDocument());
     contents->setIsUsedFromTextCache();
     styleSheet = CSSStyleSheet::createInline(contents, element, startPosition);
   }
 
   DCHECK(styleSheet);
   if (!element.isInShadowTree()) {
     styleSheet->setTitle(element.title());
-    setPreferredStylesheetSetNameIfNotSet(element.title(),
-                                          DontUpdateActiveSheets);
+    setPreferredStylesheetSetNameIfNotSet(element.title());
   }
   return styleSheet;
 }
 
 CSSStyleSheet* StyleEngine::parseSheet(Element& element,
                                        const String& text,
                                        TextPosition startPosition) {
   CSSStyleSheet* styleSheet = nullptr;
   styleSheet = CSSStyleSheet::createInline(element, KURL(), startPosition,
                                            document().characterSet());
@@ skipping 54 matching lines @@
     return true;
   return element.parentNode()->getStyleChangeType() >= SubtreeStyleChange;
 }
 
 void StyleEngine::classChangedForElement(const SpaceSplitString& changedClasses,
                                          Element& element) {
   if (shouldSkipInvalidationFor(element))
     return;
   InvalidationLists invalidationLists;
   unsigned changedSize = changedClasses.size();
-  // TODO(rune@opera.com): ensureResolver() can be removed once stylesheet
-  // updates are async. https://crbug.com/567021
-  ensureResolver();
   const RuleFeatureSet& features = ruleFeatureSet();
   for (unsigned i = 0; i < changedSize; ++i) {
     features.collectInvalidationSetsForClass(invalidationLists, element,
                                              changedClasses[i]);
   }
   m_styleInvalidator.scheduleInvalidationSetsForNode(invalidationLists,
                                                      element);
 }
 
 void StyleEngine::classChangedForElement(const SpaceSplitString& oldClasses,
                                          const SpaceSplitString& newClasses,
                                          Element& element) {
   if (shouldSkipInvalidationFor(element))
     return;
 
   if (!oldClasses.size()) {
     classChangedForElement(newClasses, element);
     return;
   }
 
   // Class vectors tend to be very short. This is faster than using a hash
   // table.
   BitVector remainingClassBits;
   remainingClassBits.ensureSize(oldClasses.size());
 
   InvalidationLists invalidationLists;
-  // TODO(rune@opera.com): ensureResolver() can be removed once stylesheet
-  // updates are async. https://crbug.com/567021
-  ensureResolver();
   const RuleFeatureSet& features = ruleFeatureSet();
 
   for (unsigned i = 0; i < newClasses.size(); ++i) {
     bool found = false;
     for (unsigned j = 0; j < oldClasses.size(); ++j) {
       if (newClasses[i] == oldClasses[j]) {
         // Mark each class that is still in the newClasses so we can skip doing
         // an n^2 search below when looking for removals. We can't break from
         // this loop early since a class can appear more than once.
         remainingClassBits.quickSet(j);
@@ skipping 18 matching lines @@
   m_styleInvalidator.scheduleInvalidationSetsForNode(invalidationLists,
                                                      element);
 }
 
 void StyleEngine::attributeChangedForElement(const QualifiedName& attributeName,
                                              Element& element) {
   if (shouldSkipInvalidationFor(element))
     return;
 
   InvalidationLists invalidationLists;
-  // TODO(rune@opera.com): ensureResolver() can be removed once stylesheet
-  // updates are async. https://crbug.com/567021
-  ensureResolver();
   ruleFeatureSet().collectInvalidationSetsForAttribute(invalidationLists,
                                                        element, attributeName);
   m_styleInvalidator.scheduleInvalidationSetsForNode(invalidationLists,
                                                      element);
 }
 
 void StyleEngine::idChangedForElement(const AtomicString& oldId,
                                       const AtomicString& newId,
                                       Element& element) {
   if (shouldSkipInvalidationFor(element))
     return;
 
   InvalidationLists invalidationLists;
-  // TODO(rune@opera.com): ensureResolver() can be removed once stylesheet
-  // updates are async. https://crbug.com/567021
-  ensureResolver();
   const RuleFeatureSet& features = ruleFeatureSet();
   if (!oldId.isEmpty())
     features.collectInvalidationSetsForId(invalidationLists, element, oldId);
   if (!newId.isEmpty())
     features.collectInvalidationSetsForId(invalidationLists, element, newId);
   m_styleInvalidator.scheduleInvalidationSetsForNode(invalidationLists,
                                                      element);
 }
 
 void StyleEngine::pseudoStateChangedForElement(
     CSSSelector::PseudoType pseudoType,
     Element& element) {
   if (shouldSkipInvalidationFor(element))
     return;
 
   InvalidationLists invalidationLists;
-  // TODO(rune@opera.com): ensureResolver() can be removed once stylesheet
-  // updates are async. https://crbug.com/567021
-  ensureResolver();
   ruleFeatureSet().collectInvalidationSetsForPseudoClass(invalidationLists,
                                                          element, pseudoType);
   m_styleInvalidator.scheduleInvalidationSetsForNode(invalidationLists,
                                                      element);
 }
 
 void StyleEngine::scheduleSiblingInvalidationsForElement(
     Element& element,
     ContainerNode& schedulingParent,
     unsigned minDirectAdjacent) {
   DCHECK(minDirectAdjacent);
 
   InvalidationLists invalidationLists;
 
-  // TODO(rune@opera.com): ensureResolver() can be removed once stylesheet
-  // updates are async. https://crbug.com/567021
-  ensureResolver();
   const RuleFeatureSet& features = ruleFeatureSet();
 
   if (element.hasID()) {
     features.collectSiblingInvalidationSetForId(invalidationLists, element,
                                                 element.idForStyleResolution(),
                                                 minDirectAdjacent);
   }
 
   if (element.hasClass()) {
     const SpaceSplitString& classNames = element.classNames();
@@ skipping 49 matching lines @@
   scheduleSiblingInvalidationsForElement(removedElement, *schedulingParent, 1);
 
   for (unsigned i = 1; beforeElement && i <= affectedSiblings;
        i++, beforeElement = ElementTraversal::previousSibling(*beforeElement))
     scheduleSiblingInvalidationsForElement(*beforeElement, *schedulingParent,
                                            i);
 }
 
 void StyleEngine::scheduleNthPseudoInvalidations(ContainerNode& nthParent) {
   InvalidationLists invalidationLists;
-  // TODO(rune@opera.com): ensureResolver() can be removed once stylesheet
-  // updates are async. https://crbug.com/567021
-  ensureResolver();
   ruleFeatureSet().collectNthInvalidationSet(invalidationLists);
   m_styleInvalidator.scheduleInvalidationSetsForNode(invalidationLists,
                                                      nthParent);
 }
 
 void StyleEngine::scheduleRuleSetInvalidationsForElement(
     Element& element,
     const HeapVector<Member<RuleSet>>& ruleSets) {
   AtomicString id;
   const SpaceSplitString* classNames = nullptr;
@@ skipping 77 matching lines @@
   if (!enabled) {
     m_styleResolverStats = nullptr;
     return;
   }
   if (!m_styleResolverStats)
     m_styleResolverStats = StyleResolverStats::create();
   else
     m_styleResolverStats->reset();
 }
 
-void StyleEngine::setPreferredStylesheetSetNameIfNotSet(
-    const String& name,
-    ActiveSheetsUpdate activeSheetsUpdate) {
+void StyleEngine::setPreferredStylesheetSetNameIfNotSet(const String& name) {
   if (!m_preferredStylesheetSetName.isEmpty())
     return;
   m_preferredStylesheetSetName = name;
   // TODO(rune@opera.com): Setting the selected set here is wrong if the set
   // has been previously set by through Document.selectedStylesheetSet. Our
   // current implementation ignores the effect of Document.selectedStylesheetSet
   // and either only collects persistent style, or additionally preferred
   // style when present.
   m_selectedStylesheetSetName = name;
-
-  // TODO(rune@opera.com): For async stylesheet update, we should always mark
-  // the TreeScope dirty here, and the synchronous active stylesheet update
-  // (resolverChanged) should go away.
-  if (activeSheetsUpdate == UpdateActiveSheets) {
-    markDocumentDirty();
-    resolverChanged(AnalyzedStyleUpdate);
-  }
+  markDocumentDirty();
 }
 
 void StyleEngine::setSelectedStylesheetSetName(const String& name) {
   m_selectedStylesheetSetName = name;
   // TODO(rune@opera.com): Setting Document.selectedStylesheetSet currently
   // has no other effect than the ability to read back the set value using
   // the same api. If it did have an effect, we should have marked the
   // document scope dirty and triggered an update of the active stylesheets
   // from here.
 }
 
 void StyleEngine::setHttpDefaultStyle(const String& content) {
-  setPreferredStylesheetSetNameIfNotSet(content, UpdateActiveSheets);
+  setPreferredStylesheetSetNameIfNotSet(content);
 }
 
 void StyleEngine::ensureUAStyleForFullscreen() {
   if (m_globalRuleSet.hasFullscreenUAStyle())
     return;
   CSSDefaultStyleSheets::instance().ensureDefaultStyleSheetForFullscreen();
   m_globalRuleSet.markDirty();
   m_globalRuleSet.update(document());
 }
 
@@ skipping 12 matching lines @@
 void StyleEngine::initialViewportChanged() {
   if (m_viewportResolver)
     m_viewportResolver->initialViewportChanged();
 }
 
 void StyleEngine::viewportRulesChanged() {
   if (m_viewportResolver)
     m_viewportResolver->setNeedsCollectRules();
 }
 
-void StyleEngine::importRemoved() {
+void StyleEngine::importAddedOrRemoved() {
   if (document().importLoader()) {
-    document().importsController()->master()->styleEngine().importRemoved();
+    document()
+        .importsController()
+        ->master()
+        ->styleEngine()
+        .importAddedOrRemoved();
     return;
   }
 
   // When we remove an import link and re-insert it into the document, the
   // import Document and CSSStyleSheet pointers are persisted. That means the
   // comparison of active stylesheets is not able to figure out that the order
   // of the stylesheets have changed after insertion.
   //
   // Fall back to re-add all sheets to the scoped resolver and recalculate style
   // for the whole document if we remove an import in case it is re-inserted
   // into the document. The assumption is that removing html imports is very
   // rare.
   if (ScopedStyleResolver* resolver = document().scopedStyleResolver()) {
+    markDocumentDirty();
     resolver->setNeedsAppendAllSheets();
     document().setNeedsStyleRecalc(
         SubtreeStyleChange, StyleChangeReasonForTracing::create(
                                 StyleChangeReason::ActiveStylesheetsUpdate));
   }
 }
 
 PassRefPtr<ComputedStyle> StyleEngine::findSharedStyle(
     const ElementResolveContext& elementResolveContext) {
   DCHECK(m_resolver);
@@ skipping 152 matching lines @@
 }
 
 DEFINE_TRACE_WRAPPERS(StyleEngine) {
   for (auto sheet : m_injectedAuthorStyleSheets) {
     visitor->traceWrappers(sheet);
   }
   visitor->traceWrappers(m_documentStyleSheetCollection);
 }
 
 }  // namespace blink