bug#56561: 29.0.50; Infloop in try_window

[Eli Zaretskii]

> From: Po Lu <luangruo@yahoo.com>
> Cc: mwd@md5i.com,  56561@debbugs.gnu.org
> Date: Sat, 16 Jul 2022 16:47:19 +0800
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > Then it's what the user or the application who set the values wanted,
> > and we shouldn't override that.  And in this case having try_window
> > return zero is perfectly OK, btw, even if it didn't process through
> > ZV.
> 
> The point I was making was that aborting in such a situation (when there
> is no row where ends_at_zv_p is true) will result in false positives
> when the tooltip is intentionally too small to display the entire text.

Yes, and so this situation should be detected, and we should avoid
triggering the assertion violation in that case.