Use nullptr_t for RefPtr, PassRefPtr and RawPtr.

Source/bindings/v8/V8EventListenerList.h

 /*
  * Copyright (C) 2009 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 32 matching lines @@
     ListenerFindOrCreate,
 };
 
 // This is a container for V8EventListener objects that uses hidden properties of v8::Object to speed up lookups.
 class V8EventListenerList {
 public:
     static PassRefPtr<V8EventListener> findWrapper(v8::Local<v8::Value> value, v8::Isolate* isolate)
     {
         ASSERT(isolate->InContext());
         if (!value->IsObject())
-            return 0;
+            return nullptr;
 
         v8::Handle<v8::String> wrapperProperty = getHiddenProperty(false, isolate);
         return doFindWrapper(v8::Local<v8::Object>::Cast(value), wrapperProperty, isolate);
     }
 
     template<typename WrapperType>
     static PassRefPtr<V8EventListener> findOrCreateWrapper(v8::Local<v8::Value>, bool isAttribute, v8::Isolate*);
 
     static void clearWrapper(v8::Handle<v8::Object> listenerObject, bool isAttribute, v8::Isolate* isolate)
     {
@@ skipping 20 matching lines @@
     }
 };
 
 template<typename WrapperType>
 PassRefPtr<V8EventListener> V8EventListenerList::findOrCreateWrapper(v8::Local<v8::Value> value, bool isAttribute, v8::Isolate* isolate)
 {
     ASSERT(isolate->InContext());
     if (!value->IsObject()
         // Non-callable attribute setter input is treated as null (no wrapper)
         || (isAttribute && !value->IsFunction()))
-        return 0;
+        return nullptr;
 
     v8::Local<v8::Object> object = v8::Local<v8::Object>::Cast(value);
     v8::Handle<v8::String> wrapperProperty = getHiddenProperty(isAttribute, isolate);
 
     V8EventListener* wrapper = doFindWrapper(object, wrapperProperty, isolate);
     if (wrapper)
         return wrapper;
 
     RefPtr<V8EventListener> wrapperPtr = WrapperType::create(object, isAttribute, isolate);
     if (wrapperPtr)
         setHiddenValue(isolate, object, wrapperProperty, v8::External::New(isolate, wrapperPtr.get()));
 
     return wrapperPtr;
 }
 
 } // namespace WebCore
 
 #endif // V8EventListenerList_h