WTF::notFound looks too much like a local variable.

Source/core/html/HTMLDimension.cpp

 /*
  * Copyright (C) 2013 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 102 matching lines @@
     // HTML5's split doesn't return a token for an empty string so
     // we need to match them here.
     if (trimmedString.isEmpty())
         return Vector<HTMLDimension>();
 
     // Step 3. To avoid String copies, we just look for commas instead of splitting.
     Vector<HTMLDimension> parsedDimensions;
     size_t lastParsedIndex = 0;
     while (true) {
         size_t nextComma = trimmedString.find(comma, lastParsedIndex);
-        if (nextComma == notFound)
+        if (nextComma == kNotFound)
             break;
 
         parsedDimensions.append(parseDimension(trimmedString, lastParsedIndex, nextComma));
         lastParsedIndex = nextComma + 1;
     }
 
     parsedDimensions.append(parseDimension(trimmedString, lastParsedIndex, trimmedString.length()));
     return parsedDimensions;
 }
 
 } // namespace WebCore