Don't update global ruleset when active style is dirty.

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

Index: third_party/WebKit/Source/core/dom/StyleEngine.cpp
diff --git a/third_party/WebKit/Source/core/dom/StyleEngine.cpp b/third_party/WebKit/Source/core/dom/StyleEngine.cpp
index 3a9d1ad294d161fd6675adcda68f61496075f5e1..816010b54390405272d091a7a1f8c78aec422b87 100644
--- a/third_party/WebKit/Source/core/dom/StyleEngine.cpp
+++ b/third_party/WebKit/Source/core/dom/StyleEngine.cpp
@@ -355,7 +355,7 @@ void StyleEngine::updateActiveStyle() {
   DCHECK(document().isActive());
   updateViewport();
   updateActiveStyleSheets();
-  m_globalRuleSet.update(document());
+  updateGlobalRuleSet();
 }
 
 const ActiveStyleSheetVector StyleEngine::activeStyleSheetsForInspector() {
@@ -931,14 +931,14 @@ void StyleEngine::ensureUAStyleForFullscreen() {
     return;
   CSSDefaultStyleSheets::instance().ensureDefaultStyleSheetForFullscreen();
   m_globalRuleSet.markDirty();
-  m_globalRuleSet.update(document());
+  updateActiveStyle();
 }
 
 void StyleEngine::ensureUAStyleForElement(const Element& element) {
   if (CSSDefaultStyleSheets::instance().ensureDefaultStyleSheetsForElement(
           element)) {
     m_globalRuleSet.markDirty();
-    m_globalRuleSet.update(document());
+    updateActiveStyle();
   }
 }