Use nullptr_t for RefPtr, PassRefPtr and RawPtr.

Source/wtf/text/AtomicString.cpp

 /*
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Patrick Gansterer <paroga@paroga.com>
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * 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
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 124 matching lines @@
     {
         location = StringImpl::create(c).leakRef();
         location->setHash(hash);
         location->setIsAtomic(true);
     }
 };
 
 PassRefPtr<StringImpl> AtomicString::add(const LChar* c)
 {
     if (!c)
-        return 0;
+        return nullptr;
     if (!*c)
         return StringImpl::empty();
 
     return addToStringTable<const LChar*, CStringTranslator>(c);
 }
 
 template<typename CharacterType>
 struct HashTranslatorCharBuffer {
     const CharacterType* s;
     unsigned length;
@@ skipping 113 matching lines @@
 
         location = newString.release().leakRef();
         location->setHash(hash);
         location->setIsAtomic(true);
     }
 };
 
 PassRefPtr<StringImpl> AtomicString::add(const UChar* s, unsigned length)
 {
     if (!s)
-        return 0;
+        return nullptr;
 
     if (!length)
         return StringImpl::empty();
 
     UCharBuffer buffer = { s, length };
     return addToStringTable<UCharBuffer, UCharBufferTranslator>(buffer);
 }
 
 PassRefPtr<StringImpl> AtomicString::add(const UChar* s, unsigned length, unsigned existingHash)
 {
     ASSERT(s);
     ASSERT(existingHash);
 
     if (!length)
         return StringImpl::empty();
 
     HashAndCharacters<UChar> buffer = { existingHash, s, length };
     return addToStringTable<HashAndCharacters<UChar>, HashAndCharactersTranslator<UChar> >(buffer);
 }
 
 PassRefPtr<StringImpl> AtomicString::add(const UChar* s)
 {
     if (!s)
-        return 0;
+        return nullptr;
 
     unsigned length = 0;
     while (s[length] != UChar(0))
         ++length;
 
     if (!length)
         return StringImpl::empty();
 
     UCharBuffer buffer = { s, length };
     return addToStringTable<UCharBuffer, UCharBufferTranslator>(buffer);
@@ skipping 24 matching lines @@
     {
         location = buffer.baseString->substring(buffer.start, buffer.length).leakRef();
         location->setHash(hash);
         location->setIsAtomic(true);
     }
 };
 
 PassRefPtr<StringImpl> AtomicString::add(StringImpl* baseString, unsigned start, unsigned length)
 {
     if (!baseString)
-        return 0;
+        return nullptr;
 
     if (!length || start >= baseString->length())
         return StringImpl::empty();
 
     unsigned maxLength = baseString->length() - start;
     if (length >= maxLength) {
         if (!start)
             return add(baseString);
         length = maxLength;
     }
@@ skipping 38 matching lines @@
     {
         location = StringImpl::create(buf.s, buf.length).leakRef();
         location->setHash(hash);
         location->setIsAtomic(true);
     }
 };
 
 PassRefPtr<StringImpl> AtomicString::add(const LChar* s, unsigned length)
 {
     if (!s)
-        return 0;
+        return nullptr;
 
     if (!length)
         return StringImpl::empty();
 
     LCharBuffer buffer = { s, length };
     return addToStringTable<LCharBuffer, LCharBufferTranslator>(buffer);
 }
 
 PassRefPtr<StringImpl> AtomicString::addFromLiteralData(const char* characters, unsigned length)
 {
@@ skipping 108 matching lines @@
 }
 
 #ifndef NDEBUG
 void AtomicString::show() const
 {
     m_string.show();
 }
 #endif
 
 } // namespace WTF