Improve DEFINE_STATIC_LOCAL()'s handling of Blink GCed objects.

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

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Research In Motion Limited. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. 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,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
 */
 
 #include "core/css/StylePropertySerializer.h"
 
 #include "core/CSSValueKeywords.h"
 #include "core/StylePropertyShorthand.h"
 #include "core/css/CSSCustomPropertyDeclaration.h"
 #include "core/css/CSSPropertyMetadata.h"
 #include "core/css/CSSValuePool.h"
+#include "wtf/StdLibExtras.h"
 #include "wtf/text/StringBuilder.h"
 #include <bitset>
 
 namespace blink {
 
 static bool isInitialOrInherit(const String& value)
 {
     return value.length() == 7 && (value == "initial" || value == "inherit");
 }
 
@@ skipping 809 matching lines @@
         result.append(value);
     }
     if (isInitialOrInherit(commonValue))
         return commonValue;
     return result.isEmpty() ? String() : result.toString();
 }
 
 static void appendBackgroundRepeatValue(StringBuilder& builder, const CSSValue& repeatXCSSValue, const CSSValue& repeatYCSSValue)
 {
     // FIXME: Ensure initial values do not appear in CSS_VALUE_LISTS.
-    DEFINE_STATIC_REF_WILL_BE_PERSISTENT(CSSPrimitiveValue, initialRepeatValue, (CSSPrimitiveValue::createIdentifier(CSSValueRepeat)));
-    const CSSPrimitiveValue& repeatX = repeatXCSSValue.isInitialValue() ? *initialRepeatValue : toCSSPrimitiveValue(repeatXCSSValue);
-    const CSSPrimitiveValue& repeatY = repeatYCSSValue.isInitialValue() ? *initialRepeatValue : toCSSPrimitiveValue(repeatYCSSValue);
+    DEFINE_STATIC_LOCAL(CSSPrimitiveValue, initialRepeatValue, (CSSPrimitiveValue::createIdentifier(CSSValueRepeat)));
+    const CSSPrimitiveValue& repeatX = repeatXCSSValue.isInitialValue() ? initialRepeatValue : toCSSPrimitiveValue(repeatXCSSValue);
+    const CSSPrimitiveValue& repeatY = repeatYCSSValue.isInitialValue() ? initialRepeatValue : toCSSPrimitiveValue(repeatYCSSValue);
     CSSValueID repeatXValueId = repeatX.getValueID();
     CSSValueID repeatYValueId = repeatY.getValueID();
     if (repeatXValueId == repeatYValueId) {
         builder.append(repeatX.cssText());
     } else if (repeatXValueId == CSSValueNoRepeat && repeatYValueId == CSSValueRepeat) {
         builder.appendLiteral("repeat-y");
     } else if (repeatXValueId == CSSValueRepeat && repeatYValueId == CSSValueNoRepeat) {
         builder.appendLiteral("repeat-x");
     } else {
         builder.append(repeatX.cssText());
@@ skipping 140 matching lines @@
             isInitialValue = false;
         if (!value->isInheritedValue())
             isInheritedValue = false;
         if (isImportant != m_propertySet.propertyIsImportant(shorthand.properties()[i]))
             return false;
     }
     return isInitialValue || isInheritedValue;
 }
 
 } // namespace blink