Use nullptr_t for RefPtr, PassRefPtr and RawPtr.

Source/core/css/CSSFontFace.cpp

 /*
  * Copyright (C) 2007, 2008, 2011 Apple 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 69 matching lines @@
         }
     }
 
     if (m_segmentedFontFace)
         m_segmentedFontFace->fontLoaded(this);
 }
 
 PassRefPtr<SimpleFontData> CSSFontFace::getFontData(const FontDescription& fontDescription)
 {
     if (!isValid())
-        return 0;
+        return nullptr;
 
     while (!m_sources.isEmpty()) {
         OwnPtr<CSSFontFaceSource>& source = m_sources.first();
         if (RefPtr<SimpleFontData> result = source->getFontData(fontDescription)) {
             if (loadStatus() == FontFace::Unloaded && (source->isLoading() || source->isLoaded()))
                 setLoadStatus(FontFace::Loading);
             if (loadStatus() == FontFace::Loading && source->isLoaded())
                 setLoadStatus(FontFace::Loaded);
             return result.release();
         }
         m_sources.removeFirst();
     }
 
     if (loadStatus() == FontFace::Unloaded)
         setLoadStatus(FontFace::Loading);
     if (loadStatus() == FontFace::Loading)
         setLoadStatus(FontFace::Error);
-    return 0;
+    return nullptr;
 }
 
 void CSSFontFace::willUseFontData(const FontDescription& fontDescription)
 {
     // Kicks off font load here only if the @font-face has no unicode-range.
     // @font-faces with unicode-range will be loaded when a GlyphPage for the
     // font is created.
     // FIXME: Pass around the text to render from RenderText, and kick download
     // if m_ranges intersects with the text. Make sure this does not cause
     // performance regression.
@@ skipping 94 matching lines @@
         UChar32 c = text.characterStartingAt(index);
         index += U16_LENGTH(c);
         Vector<UnicodeRange>::const_iterator it = std::lower_bound(m_ranges.begin(), m_ranges.end(), c);
         if (it != m_ranges.end() && it->contains(c))
             return true;
     }
     return false;
 }
 
 }