StyleResolver should update RuleSets lazily.

Source/core/inspector/InspectorCSSAgent.cpp

 /*
  * Copyright (C) 2010, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 938 matching lines @@
     // A non-active document has no styles.
     if (!ownerDocument->isActive())
         return;
 
     // FIXME: It's really gross for the inspector to reach in and access StyleResolver
     // directly here. We need to provide the Inspector better APIs to get this information
     // without grabbing at internal style classes!
 
     // Matched rules.
     StyleResolver* styleResolver = ownerDocument->styleResolver();
+    appendPendingStyleSheetsIfNeeded(styleResolver);
     // FIXME: This code should not pass DoNotIncludeStyleSheetInCSSOMWrapper. All CSSOMWrappers should always have a parent sheet or rule.
     RefPtr<CSSRuleList> matchedRules = styleResolver->pseudoCSSRulesForElement(element, elementPseudoId, StyleResolver::AllCSSRules, DoNotIncludeStyleSheetInCSSOMWrapper);
     matchedCSSRules = buildArrayForMatchedRuleList(matchedRules.get(), styleResolver, originalElement);
 
     // Pseudo elements.
     if (!elementPseudoId && (!includePseudo || *includePseudo)) {
         RefPtr<TypeBuilder::Array<TypeBuilder::CSS::PseudoIdMatches> > pseudoElements = TypeBuilder::Array<TypeBuilder::CSS::PseudoIdMatches>::create();
         for (PseudoId pseudoId = FIRST_PUBLIC_PSEUDOID; pseudoId < AFTER_LAST_INTERNAL_PSEUDOID; pseudoId = static_cast<PseudoId>(pseudoId + 1)) {
             RefPtr<CSSRuleList> matchedRules = styleResolver->pseudoCSSRulesForElement(element, pseudoId, StyleResolver::AllCSSRules, DoNotIncludeStyleSheetInCSSOMWrapper);
             if (matchedRules && matchedRules->length()) {
                 RefPtr<TypeBuilder::CSS::PseudoIdMatches> matches = TypeBuilder::CSS::PseudoIdMatches::create()
                     .setPseudoId(static_cast<int>(pseudoId))
                     .setMatches(buildArrayForMatchedRuleList(matchedRules.get(), styleResolver, element));
                 pseudoElements->addItem(matches.release());
             }
         }
 
         pseudoIdMatches = pseudoElements.release();
     }
 
     // Inherited styles.
     if (!elementPseudoId && (!includeInherited || *includeInherited)) {
         RefPtr<TypeBuilder::Array<TypeBuilder::CSS::InheritedStyleEntry> > entries = TypeBuilder::Array<TypeBuilder::CSS::InheritedStyleEntry>::create();
         Element* parentElement = element->parentElement();
         while (parentElement) {
             StyleResolver* parentStyleResolver = parentElement->ownerDocument()->styleResolver();
+            appendPendingStyleSheetsIfNeeded(parentStyleResolver);
             RefPtr<CSSRuleList> parentMatchedRules = parentStyleResolver->cssRulesForElement(parentElement, StyleResolver::AllCSSRules, DoNotIncludeStyleSheetInCSSOMWrapper);
             RefPtr<TypeBuilder::CSS::InheritedStyleEntry> entry = TypeBuilder::CSS::InheritedStyleEntry::create()
                 .setMatchedCSSRules(buildArrayForMatchedRuleList(parentMatchedRules.get(), styleResolver, parentElement));
             if (parentElement->style() && parentElement->style()->length()) {
                 InspectorStyleSheetForInlineStyle* styleSheet = asInspectorStyleSheet(parentElement);
                 if (styleSheet)
                     entry->setInlineStyle(styleSheet->buildObjectForStyle(styleSheet->styleForId(InspectorCSSId(styleSheet->id(), 0))));
             }
 
             entries->addItem(entry.release());
@@ skipping 105 matching lines @@
 
 void InspectorCSSAgent::getStyleSheet(ErrorString* errorString, const String& styleSheetId, RefPtr<TypeBuilder::CSS::CSSStyleSheetBody>& styleSheetObject)
 {
     InspectorStyleSheet* inspectorStyleSheet = assertStyleSheetForId(errorString, styleSheetId);
     if (!inspectorStyleSheet)
         return;
 
     Document* doc = inspectorStyleSheet->pageStyleSheet() ? inspectorStyleSheet->pageStyleSheet()->ownerDocument() : 0;
     if (!doc || !doc->styleResolver())
         return;
+    appendPendingStyleSheetsIfNeeded(doc->styleResolver());
 
     RefPtr<TypeBuilder::CSS::CSSStyleSheetBody> result = TypeBuilder::CSS::CSSStyleSheetBody::create()
         .setStyleSheetId(styleSheetId)
         .setRules(buildArrayForRuleList(inspectorStyleSheet->pageStyleSheet()->rules().get(), doc->styleResolver()));
 
     bool success = inspectorStyleSheet->fillObjectForStyleSheet(result);
     if (success)
         styleSheetObject = result;
 }
 
@@ skipping 653 matching lines @@
             documentsToChange.add(element->ownerDocument());
     }
 
     m_nodeIdToForcedPseudoState.clear();
     for (HashSet<Document*>::iterator it = documentsToChange.begin(), end = documentsToChange.end(); it != end; ++it)
         (*it)->setNeedsStyleRecalc();
 }
 
 } // namespace WebCore