Make updateStyleAndLayoutTree ready for async stylesheet update.

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 101 matching lines @@
 
   StyleSheetCollectionMap::iterator it =
       m_styleSheetCollectionMap.find(&treeScope);
   if (it == m_styleSheetCollectionMap.end())
     return nullptr;
   return it->value.get();
 }
 
 const HeapVector<TraceWrapperMember<StyleSheet>>&
 StyleEngine::styleSheetsForStyleSheetList(TreeScope& treeScope) {
+  // TODO(rune@opera.com): we could split styleSheets and active stylesheet
+  // update to have a lighter update while accessing the styleSheets list.
+  DCHECK(master());
+  if (master()->isActive()) {
+    if (isMaster())
+      updateActiveStyle();
+    else
+      master()->styleEngine().updateActiveStyle();
+  }
+
   if (treeScope == m_document)
     return documentStyleSheetCollection().styleSheetsForStyleSheetList();
 
   return ensureStyleSheetCollectionFor(treeScope)
       ->styleSheetsForStyleSheetList();
 }
 
 void StyleEngine::injectAuthorSheet(StyleSheetContents* authorSheet) {
   m_injectedAuthorStyleSheets.append(TraceWrapperMember<CSSStyleSheet>(
       this, CSSStyleSheet::create(authorSheet, *m_document)));
@@ skipping 194 matching lines @@
     for (TreeScope* treeScope : treeScopesRemoved)
       m_activeTreeScopes.remove(treeScope);
   }
 
   InspectorInstrumentation::activeStyleSheetsUpdated(m_document);
 
   m_dirtyTreeScopes.clear();
   m_documentScopeDirty = 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();
+}
+
+void StyleEngine::updateActiveStyle() {
+  updateViewport();
+  updateActiveStyleSheets();
+  m_globalRuleSet.update(document());
+}
+
 const HeapVector<Member<CSSStyleSheet>>
 StyleEngine::activeStyleSheetsForInspector() const {
   if (m_activeTreeScopes.isEmpty())
     return documentStyleSheetCollection().activeAuthorStyleSheets();
 
   HeapVector<Member<CSSStyleSheet>> activeStyleSheets;
 
   activeStyleSheets.appendVector(
       documentStyleSheetCollection().activeAuthorStyleSheets());
   for (TreeScope* treeScope : m_activeTreeScopes) {
@@ skipping 46 matching lines @@
   m_globalRuleSet.update(document());
 
   if (!document().layoutViewItem().isNull() &&
       document().layoutViewItem().style())
     document().layoutViewItem().style()->font().update(fontSelector());
 }
 
 void StyleEngine::appendActiveAuthorStyleSheets() {
   DCHECK(isMaster());
 
-  viewportRulesChanged();
-
   m_resolver->appendAuthorStyleSheets(
       documentStyleSheetCollection().activeAuthorStyleSheets());
   for (TreeScope* treeScope : m_activeTreeScopes) {
     if (TreeScopeStyleSheetCollection* collection =
             m_styleSheetCollectionMap.get(treeScope))
       m_resolver->appendAuthorStyleSheets(
           collection->activeAuthorStyleSheets());
   }
 }
 
@@ skipping 115 matching lines @@
     markDocumentDirty();
     return;
   }
 
   DCHECK(m_styleSheetCollectionMap.contains(&scope));
   m_dirtyTreeScopes.add(&scope);
 }
 
 void StyleEngine::markDocumentDirty() {
   m_documentScopeDirty = true;
+  if (RuntimeEnabledFeatures::cssViewportEnabled())
+    viewportRulesChanged();
   if (document().importLoader())
     document().importsController()->master()->styleEngine().markDocumentDirty();
 }
 
 CSSStyleSheet* StyleEngine::createSheet(Element& element,
                                         const String& text,
                                         TextPosition startPosition,
                                         StyleEngineContext& context) {
   DCHECK(element.document() == document());
   CSSStyleSheet* styleSheet = nullptr;
@@ skipping 442 matching lines @@
     m_globalRuleSet.markDirty();
     m_globalRuleSet.update(document());
   }
 }
 
 bool StyleEngine::hasRulesForId(const AtomicString& id) const {
   return m_globalRuleSet.ruleFeatureSet().hasSelectorForId(id);
 }
 
 void StyleEngine::initialViewportChanged() {
-  if (!m_viewportResolver)
-    return;
-
-  m_viewportResolver->initialViewportChanged();
-
-  // TODO(rune@opera.com): for async stylesheet update, updateViewport() should
-  // be called as part of the lifecycle update for active style. Synchronous for
-  // now.
-  m_viewportResolver->updateViewport(documentStyleSheetCollection());
+  if (m_viewportResolver)
+    m_viewportResolver->initialViewportChanged();
 }
 
 void StyleEngine::viewportRulesChanged() {
-  if (!m_viewportResolver)
-    return;
-  m_viewportResolver->setNeedsCollectRules();
-
-  // TODO(rune@opera.com): for async stylesheet update, updateViewport() should
-  // be called as part of the lifecycle update for active style. Synchronous for
-  // now.
-  m_viewportResolver->updateViewport(documentStyleSheetCollection());
+  if (m_viewportResolver)
+    m_viewportResolver->setNeedsCollectRules();
 }
 
 PassRefPtr<ComputedStyle> StyleEngine::findSharedStyle(
     const ElementResolveContext& elementResolveContext) {
   DCHECK(m_resolver);
   return SharedStyleFinder(
              elementResolveContext, m_globalRuleSet.ruleFeatureSet(),
              m_globalRuleSet.siblingRuleSet(),
              m_globalRuleSet.uncommonAttributeRuleSet(), *m_resolver)
       .findSharedStyle();
@@ skipping 110 matching lines @@
 }
 
 DEFINE_TRACE_WRAPPERS(StyleEngine) {
   for (auto sheet : m_injectedAuthorStyleSheets) {
     visitor->traceWrappers(sheet);
   }
   visitor->traceWrappers(m_documentStyleSheetCollection);
 }
 
 }  // namespace blink