bug#16411: undo-only bugs

[Stefan Monnier]

>> Actually, this makes me realize the solution to bug 1 is inadequate.
>> Calling (undo-primitive 1) N times creates N redo records whereas
>> (undo-primitive N) creates one.
> No, primitive-undo does not add any undo boundary.

Actually, now I'm not sure what you meant by "redo records".
(primitive-undo N) will undo all the M "records" that appear before the
next Nth undo boundary, and will correspondingly add M redo "records",
but no boundary.


        Stefan