key handlers

[Ranson <ranson@LANNION.cnet.fr>]

I have a problem with the way enter/exit-key-handler are called by MCL. My
understanding is that they are useful for validating text entry, and I would
expect the following behaviour:
- When opening the dialog, call enter for the selected text item
- When selecting another text item, call exit on the current one, then enter
on the new one.
- When closing the dialog, call exit on the current text item.

This is not what I observe. The first two points are correct, but not the last
one. What I see when the dialog is closed is this:
+ If the current text item is the last one, do nothing
+ Else call exit on the current item
  + Then for all items after the current one, expect the last
    + Call enter
    + Call exit
  + For the last item, call enter (but not exit)

The effect is that if the current item is not the last, the items after it
(except the last) are validated unnecessarily, and if the current item is the
last one, it is not validated at all. Does not seem very useful to me.
BTW, this is with 2.0f2.
     Daniel.