Do not zero-initialize RawPtr.

Source/core/editing/EditingStyle.cpp

 /*
  * Copyright (C) 2007, 2008, 2009 Apple Computer, Inc.
  * Copyright (C) 2010, 2011 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
@@ skipping 276 matching lines @@
         style->setProperty(m_propertyID, value->cssText());
 }
 
 PassRefPtrWillBeRawPtr<CSSValue> HTMLAttributeEquivalent::attributeValueAsCSSValue(Element* element) const
 {
     ASSERT(element);
     const AtomicString& value = element->getAttribute(m_attrName);
     if (value.isNull())
         return nullptr;
 
-    RefPtrWillBeRawPtr<MutableStylePropertySet> dummyStyle;
+    RefPtrWillBeRawPtr<MutableStylePropertySet> dummyStyle = nullptr;
     dummyStyle = MutableStylePropertySet::create();
     dummyStyle->setProperty(m_propertyID, value);
     return dummyStyle->getPropertyCSSValue(m_propertyID);
 }
 
 class HTMLFontSizeEquivalent FINAL : public HTMLAttributeEquivalent {
 public:
     static PassOwnPtr<HTMLFontSizeEquivalent> create()
     {
         return adoptPtr(new HTMLFontSizeEquivalent());
@@ skipping 624 matching lines @@
 {
     if (!m_mutableStyle)
         return;
 
     // ReplaceSelectionCommand::handleStyleSpans() requires that this function only removes the editing style.
     // If this function was modified in the future to delete all redundant properties, then add a boolean value to indicate
     // which one of editingStyleAtPosition or computedStyle is called.
     RefPtr<EditingStyle> editingStyleAtPosition = EditingStyle::create(position, EditingPropertiesInEffect);
     StylePropertySet* styleAtPosition = editingStyleAtPosition->m_mutableStyle.get();
 
-    RefPtrWillBeRawPtr<CSSValue> unicodeBidi;
-    RefPtrWillBeRawPtr<CSSValue> direction;
+    RefPtrWillBeRawPtr<CSSValue> unicodeBidi = nullptr;
+    RefPtrWillBeRawPtr<CSSValue> direction = nullptr;
     if (shouldPreserveWritingDirection == PreserveWritingDirection) {
         unicodeBidi = m_mutableStyle->getPropertyCSSValue(CSSPropertyUnicodeBidi);
         direction = m_mutableStyle->getPropertyCSSValue(CSSPropertyDirection);
     }
 
     m_mutableStyle->removeEquivalentProperties(styleAtPosition);
 
     if (textAlignResolvingStartAndEnd(m_mutableStyle.get()) == textAlignResolvingStartAndEnd(styleAtPosition))
         m_mutableStyle->removeProperty(CSSPropertyTextAlign);
 
@@ skipping 680 matching lines @@
 {
     for (Node* ancestor = node; ancestor; ancestor = ancestor->parentNode()) {
         RefPtr<CSSComputedStyleDeclaration> ancestorStyle = CSSComputedStyleDeclaration::create(ancestor);
         if (!hasTransparentBackgroundColor(ancestorStyle.get()))
             return ancestorStyle->getPropertyCSSValue(CSSPropertyBackgroundColor);
     }
     return nullptr;
 }
 
 }