bug#15716: 24.3.50; redisplay bug for display-table update

[Drew Adams]

> `C-l' does not necessarily do a redisplay, at least not by default.
> It did so in the past, but ceased to since Emacs 23.1, where `C-l'
> was bound to 'recenter-top-bottom' instead of 'recenter'.

OK.  So the only bug is in the display, not in `C-l' not fixing the
problem.

> Emacswiki seems to be off-line.

It's back up.  It was down for a few minutes.  I reported it to the
wiki maintainer.

> But unless you are saying that
> turning on this feature _always_ results in garbled display, I will
> need a recipe to reproduce the problem, or else it is impossible to
> debug it.

No, this feature does not cause the problem.  There is apparently a
display problem that occurred this one time.  I was surprised, as I
said, because I have never seen it before.  (And I mistakenly expected
`C-l' to fix it.)  I do not have a recipe to repro it.  I was hoping 
that perhaps the description, wrt display-table modification, might
ring a bell wrt recent Emacs changes.  If not, I guess there's nothing
you can do at this point.