Do not zero-initialize RawPtr.

Source/core/css/CSSValuePool.cpp

 /*
  * Copyright (C) 2011, 2012 Apple 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 70 matching lines @@
         return m_colorWhite;
     // Just because it is common.
     if (rgbValue == Color::black)
         return m_colorBlack;
 
     // Just wipe out the cache and start rebuilding if it gets too big.
     const unsigned maximumColorCacheSize = 512;
     if (m_colorValueCache.size() > maximumColorCacheSize)
         m_colorValueCache.clear();
 
-    RefPtrWillBeRawPtr<CSSPrimitiveValue> dummyValue;
+    RefPtrWillBeRawPtr<CSSPrimitiveValue> dummyValue = nullptr;
     ColorValueCache::AddResult entry = m_colorValueCache.add(rgbValue, dummyValue);
     if (entry.isNewEntry)
         entry.storedValue->value = CSSPrimitiveValue::createColor(rgbValue);
     return entry.storedValue->value;
 }
 
 PassRefPtrWillBeRawPtr<CSSPrimitiveValue> CSSValuePool::createValue(double value, CSSPrimitiveValue::UnitTypes type)
 {
     if (value < 0 || value > maximumCacheableIntegerValue)
         return CSSPrimitiveValue::create(value, type);
@@ skipping 57 matching lines @@
     visitor->trace(m_colorWhite);
     visitor->trace(m_colorBlack);
     visitor->trace(m_pixelValueCache);
     visitor->trace(m_percentValueCache);
     visitor->trace(m_numberValueCache);
     visitor->trace(m_fontFaceValueCache);
     visitor->trace(m_fontFamilyValueCache);
 }
 
 }