Use nullptr_t for RefPtr, PassRefPtr and RawPtr.

Source/core/html/canvas/OESVertexArrayObject.cpp

 /*
  * Copyright (C) 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 39 matching lines @@
 }
 
 PassRefPtr<OESVertexArrayObject> OESVertexArrayObject::create(WebGLRenderingContext* context)
 {
     return adoptRef(new OESVertexArrayObject(context));
 }
 
 PassRefPtr<WebGLVertexArrayObjectOES> OESVertexArrayObject::createVertexArrayOES()
 {
     if (isLost())
-        return 0;
+        return nullptr;
 
     RefPtr<WebGLVertexArrayObjectOES> o = WebGLVertexArrayObjectOES::create(m_context, WebGLVertexArrayObjectOES::VaoTypeUser);
     m_context->addContextObject(o.get());
     return o.release();
 }
 
 void OESVertexArrayObject::deleteVertexArrayOES(WebGLVertexArrayObjectOES* arrayObject)
 {
     if (!arrayObject || isLost())
         return;
 
     if (!arrayObject->isDefaultObject() && arrayObject == m_context->m_boundVertexArrayObject)
-        m_context->setBoundVertexArrayObject(0);
+        m_context->setBoundVertexArrayObject(nullptr);
 
     arrayObject->deleteObject(m_context->webGraphicsContext3D());
 }
 
 GLboolean OESVertexArrayObject::isVertexArrayOES(WebGLVertexArrayObjectOES* arrayObject)
 {
     if (!arrayObject || isLost())
         return 0;
 
     if (!arrayObject->hasEverBeenBound())
@@ skipping 12 matching lines @@
         return;
     }
 
     if (arrayObject && !arrayObject->isDefaultObject() && arrayObject->object()) {
         m_context->webGraphicsContext3D()->bindVertexArrayOES(arrayObject->object());
 
         arrayObject->setHasEverBeenBound();
         m_context->setBoundVertexArrayObject(arrayObject);
     } else {
         m_context->webGraphicsContext3D()->bindVertexArrayOES(0);
-        m_context->setBoundVertexArrayObject(0);
+        m_context->setBoundVertexArrayObject(nullptr);
     }
 }
 
 bool OESVertexArrayObject::supported(WebGLRenderingContext* context)
 {
     return context->extensionsUtil()->supportsExtension("GL_OES_vertex_array_object");
 }
 
 const char* OESVertexArrayObject::extensionName()
 {
     return "OES_vertex_array_object";
 }
 
 } // namespace WebCore