Added trace for scheduleInvalidationsForRuleSets.

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 831 matching lines @@
 void StyleEngine::scheduleInvalidationsForRuleSets(
     TreeScope& treeScope,
     const HeapHashSet<Member<RuleSet>>& ruleSets) {
 #if DCHECK_IS_ON()
   // Full scope recalcs should be handled while collecting the ruleSets before
   // calling this method.
   for (auto ruleSet : ruleSets)
     DCHECK(!ruleSet->features().needsFullRecalcForRuleSetInvalidation());
 #endif  // DCHECK_IS_ON()
 
+  TRACE_EVENT0("blink,blink_style",
+               "StyleEngine::scheduleInvalidationsForRuleSets");
+
   bool invalidateSlotted = false;
   if (treeScope.rootNode().isShadowRoot()) {
     Element& host = toShadowRoot(treeScope.rootNode()).host();
     scheduleRuleSetInvalidationsForElement(host, ruleSets);
     if (host.getStyleChangeType() >= SubtreeStyleChange)
       return;
     for (auto ruleSet : ruleSets) {
       if (ruleSet->hasSlottedRules()) {
         invalidateSlotted = true;
         break;
@@ skipping 270 matching lines @@
 }
 
 DEFINE_TRACE_WRAPPERS(StyleEngine) {
   for (auto sheet : m_injectedAuthorStyleSheets) {
     visitor->traceWrappers(sheet);
   }
   visitor->traceWrappers(m_documentStyleSheetCollection);
 }
 
 }  // namespace blink