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

Source/core/editing/InputMethodController.h

 /*
  * 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 27 matching lines @@
 class Text;
 
 // FIXME: We should move PlainTextOffsets to own file for using InputMethodController
 // and TextIterator and unify PlainTextRange defined in AccessibilityObject.h.
 class PlainTextOffsets {
 public:
     PlainTextOffsets();
     PlainTextOffsets(int start, int length);
     size_t end() const { return m_end; }
     size_t start() const { return m_start; }
-    bool isNull() const { return m_start == notFound; }
+    bool isNull() const { return m_start == kNotFound; }
 private:
     size_t m_start;
     size_t m_end;
 };
 
 class InputMethodController {
 public:
     static PassOwnPtr<InputMethodController> create(Frame*);
     ~InputMethodController();
 
@@ skipping 50 matching lines @@
     void selectComposition() const;
     enum FinishCompositionMode { ConfirmComposition, CancelComposition };
     void finishComposition(const String&, FinishCompositionMode);
     PlainTextOffsets getSelectionOffsets() const;
     bool setSelectionOffsets(const PlainTextOffsets&);
 };
 
 } // namespace WebCore
 
 #endif // InputMethodController_h