This CL clean up patch in SVGElements.

Source/core/svg/SVGElement.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2008 Rob Buis <buis@kde.org>
  * Copyright (C) 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Alp Toker <alp@atoker.com>
  * Copyright (C) 2009 Cameron McCormack <cam@mcc.id.au>
  *
  * 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
@@ skipping 424 matching lines @@
 SVGSVGElement* SVGElement::ownerSVGElement() const
 {
     ContainerNode* n = parentOrShadowHostNode();
     while (n) {
         if (isSVGSVGElement(*n))
             return toSVGSVGElement(n);
 
         n = n->parentOrShadowHostNode();
     }
 
-    return 0;
+    return nullptr;
 }
 
 SVGElement* SVGElement::viewportElement() const
 {
     // This function needs shadow tree support - as LayoutSVGContainer uses this function
     // to determine the "overflow" property. <use> on <symbol> wouldn't work otherwhise.
     ContainerNode* n = parentOrShadowHostNode();
     while (n) {
         if (isSVGSVGElement(*n) || isSVGImageElement(*n) || isSVGSymbolElement(*n))
             return toSVGElement(n);
 
         n = n->parentOrShadowHostNode();
     }
 
-    return 0;
+    return nullptr;
 }
 
 SVGDocumentExtensions& SVGElement::accessDocumentSVGExtensions()
 {
     // This function is provided for use by SVGAnimatedProperty to avoid
     // global inclusion of core/dom/Document.h in SVG code.
     return document().accessSVGExtensions();
 }
 
 void SVGElement::mapInstanceToElement(SVGElement* instance)
@@ skipping 85 matching lines @@
     ASSERT(!hasSVGRareData() || !svgRareData()->correspondingElement() || containingShadowRoot());
     return hasSVGRareData() ? svgRareData()->correspondingElement() : 0;
 }
 
 SVGUseElement* SVGElement::correspondingUseElement() const
 {
     if (ShadowRoot* root = containingShadowRoot()) {
         if (isSVGUseElement(root->host()) && (root->type() == ShadowRoot::UserAgentShadowRoot))
             return toSVGUseElement(root->host());
     }
-    return 0;
+    return nullptr;
 }
 
 void SVGElement::setCorrespondingElement(SVGElement* correspondingElement)
 {
     ensureSVGRareData()->setCorrespondingElement(correspondingElement);
 }
 
 bool SVGElement::inUseShadowTree() const
 {
     return correspondingUseElement();
@@ skipping 259 matching lines @@
 }
 
 void SVGElement::svgLoadEventTimerFired(Timer<SVGElement>*)
 {
     sendSVGLoadEventIfPossible();
 }
 
 Timer<SVGElement>* SVGElement::svgLoadEventTimer()
 {
     ASSERT_NOT_REACHED();
-    return 0;
+    return nullptr;
 }
 
 void SVGElement::attributeChanged(const QualifiedName& name, const AtomicString& newValue, AttributeModificationReason)
 {
     Element::attributeChanged(name, newValue);
 
     if (isIdAttributeName(name))
         rebuildAllIncomingReferences();
 
     // Changes to the style attribute are processed lazily (see Element::getAttribute() and related methods),
@@ skipping 60 matching lines @@
             style = layoutObject->style();
     }
 
     return document().ensureStyleResolver().styleForElement(correspondingElement(), style, DisallowStyleSharing);
 }
 
 MutableStylePropertySet* SVGElement::animatedSMILStyleProperties() const
 {
     if (hasSVGRareData())
         return svgRareData()->animatedSMILStyleProperties();
-    return 0;
+    return nullptr;
 }
 
 MutableStylePropertySet* SVGElement::ensureAnimatedSMILStyleProperties()
 {
     return ensureSVGRareData()->ensureAnimatedSMILStyleProperties();
 }
 
 void SVGElement::setUseOverrideComputedStyle(bool value)
 {
     if (hasSVGRareData())
@@ skipping 171 matching lines @@
     if (name == classAttr)
         return true;
 
     return animatableAttributes.contains(name);
 }
 #endif
 
 SVGElementSet* SVGElement::setOfIncomingReferences() const
 {
     if (!hasSVGRareData())
-        return 0;
+        return nullptr;
     return &svgRareData()->incomingReferences();
 }
 
 void SVGElement::addReferenceTo(SVGElement* targetElement)
 {
     ASSERT(targetElement);
 
     ensureSVGRareData()->outgoingReferences().add(targetElement);
     targetElement->ensureSVGRareData()->incomingReferences().add(this);
 }
@@ skipping 54 matching lines @@
     Element::trace(visitor);
 }
 
 const AtomicString& SVGElement::eventParameterName()
 {
     DEFINE_STATIC_LOCAL(const AtomicString, evtString, ("evt", AtomicString::ConstructFromLiteral));
     return evtString;
 }
 
 } // namespace blink