Current work-in-progress crbug.com/567021

third_party/WebKit/Source/core/css/CSSStyleSheet.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2006, 2007, 2012 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 156 matching lines @@
 
     // Any existing CSSOM wrappers need to be connected to the copied child rules.
     reattachChildRuleCSSOMWrappers();
 }
 
 void CSSStyleSheet::didMutateRules()
 {
     ASSERT(m_contents->isMutable());
     ASSERT(m_contents->clientSize() <= 1);
 
-    didMutate(PartialRuleUpdate);
+    didMutate();
 }
 
-void CSSStyleSheet::didMutate(StyleSheetUpdateType updateType)
+void CSSStyleSheet::didMutate()
 {
     Document* owner = ownerDocument();
     if (!owner)
         return;
-
-    // Need FullStyleUpdate when insertRule or deleteRule,
-    // because StyleSheetCollection::analyzeStyleSheetChange cannot detect partial rule update.
-    StyleResolverUpdateMode updateMode = updateType != PartialRuleUpdate ? AnalyzedStyleUpdate : FullStyleUpdate;
-    owner->styleEngine().setNeedsActiveStyleUpdate(this, updateMode);
+    if (!ownerNode())
+        return;
+    if (ownerNode()->inShadowIncludingDocument())
+        owner->styleEngine().setNeedsActiveStyleUpdate(ownerNode()->treeScope());
 }
 
 void CSSStyleSheet::reattachChildRuleCSSOMWrappers()
 {
     for (unsigned i = 0; i < m_childRuleCSSOMWrappers.size(); ++i) {
         if (!m_childRuleCSSOMWrappers[i])
             continue;
         m_childRuleCSSOMWrappers[i]->reattach(m_contents->ruleAt(i));
     }
 }
 
 void CSSStyleSheet::setDisabled(bool disabled)
 {
     if (disabled == m_isDisabled)
         return;
     m_isDisabled = disabled;
 
     didMutate();
 }
 
 void CSSStyleSheet::setMediaQueries(MediaQuerySet* mediaQueries)
 {
     m_mediaQueries = mediaQueries;
     if (m_mediaCSSOMWrapper && m_mediaQueries)
         m_mediaCSSOMWrapper->reattach(m_mediaQueries.get());
 
 }
 
+bool CSSStyleSheet::matchesMediaQueries(const MediaQueryEvaluator& evaluator)
+{
+    m_viewportDependentMediaQueryResults.clear();
+    m_deviceDependentMediaQueryResults.clear();
+
+    if (!m_mediaQueries)
+        return true;
+
+    return evaluator.eval(m_mediaQueries, &m_viewportDependentMediaQueryResults, &m_deviceDependentMediaQueryResults);
+}
+
 unsigned CSSStyleSheet::length() const
 {
     return m_contents->ruleCount();
 }
 
 CSSRule* CSSStyleSheet::item(unsigned index)
 {
     unsigned ruleCount = length();
     if (index >= ruleCount)
         return nullptr;
 
     if (m_childRuleCSSOMWrappers.isEmpty())
         m_childRuleCSSOMWrappers.grow(ruleCount);
     ASSERT(m_childRuleCSSOMWrappers.size() == ruleCount);
 
     Member<CSSRule>& cssRule = m_childRuleCSSOMWrappers[index];
     if (!cssRule)
         cssRule = m_contents->ruleAt(index)->createCSSOMWrapper(this);
     return cssRule.get();
 }
 
 void CSSStyleSheet::clearOwnerNode()
 {
-    didMutate(EntireStyleSheetUpdate);
+    didMutate();
     if (m_ownerNode)
         m_contents->unregisterClient(this);
     m_ownerNode = nullptr;
 }
 
 bool CSSStyleSheet::canAccessRules() const
 {
     if (m_isInlineStylesheet)
         return true;
     KURL baseURL = m_contents->baseURL();
@@ skipping 179 matching lines @@
 
     CSSStyleSheet::RuleMutationScope mutationScope(this);
     m_contents->clearRules();
     m_contents->parseString(text);
 }
 
 DEFINE_TRACE(CSSStyleSheet)
 {
     visitor->trace(m_contents);
     visitor->trace(m_mediaQueries);
+    visitor->trace(m_viewportDependentMediaQueryResults);
+    visitor->trace(m_deviceDependentMediaQueryResults);
     visitor->trace(m_ownerNode);
     visitor->trace(m_ownerRule);
     visitor->trace(m_mediaCSSOMWrapper);
     visitor->trace(m_childRuleCSSOMWrappers);
     visitor->trace(m_ruleListCSSOMWrapper);
     StyleSheet::trace(visitor);
 }
 
 } // namespace blink