bug#16493: 24.3.50; (setq search-invisible t) is useless, let's allow to turn visible-mode temporarily on

[Eli Zaretskii]

> From: Noam Postavsky <npostavs@gmail.com>
> Date: Tue, 30 Apr 2019 00:34:41 -0400
> Cc: 16493@debbugs.gnu.org, Stefan Monnier <monnier@IRO.UMontreal.CA>
> 
> I was thinking all this complication could be avoided if we just allowed
> (overlay-put OVERLAY 'invisible nil) to make text visible.

But we already do: overlay-get returns nil in that case, and the text
is revealed, so the original code before your proposed changes already
does the job.  What am I missing?  Some context where the above
doesn't work?