Use nullptr_t for RefPtr, PassRefPtr and RawPtr.

Source/platform/fonts/GlyphPageTreeNode.cpp

 /*
  * Copyright (C) 2006, 2007, 2008 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
@@ skipping 241 matching lines @@
                             for (int j = from; j < to; j++) {
                                 if (!m_page->glyphAt(j) && pageToFill->glyphAt(j))
                                     m_page->setGlyphDataForIndex(j, pageToFill->glyphDataForIndex(j));
                             }
                         }
                     }
                 }
             }
 
             if (!haveGlyphs)
-                m_page = 0;
+                m_page = nullptr;
         } else if (parentPage && parentPage->owner() != m_parent) {
             // The page we're overriding may not be owned by our parent node.
             // This happens when our parent node provides no useful overrides
             // and just copies the pointer to an already-existing page (see
             // below).
             //
             // We want our override to be shared by all nodes that reference
             // that page to avoid duplication, and so standardize on having the
             // page's owner collect all the overrides.  Call getChild on the
             // page owner with the desired font data (this will populate
@@ skipping 155 matching lines @@
         printf("\nPage %d:\n", it->key);
         showGlyphPageTree(it->key);
     }
 }
 
 void showGlyphPageTree(unsigned pageNumber)
 {
     WebCore::GlyphPageTreeNode::getRoot(pageNumber)->showSubtree();
 }
 #endif