bug#41584: 26.3; org-indent-mode's line-prefix text property flickers near overlays

[Eli Zaretskii]

> From: Kévin Le Gouguec <kevin.legoug...@gmail.com>
> Cc: 41...@debbugs.gnu.org,  dgu...@yandex.ru
> Date: Fri, 29 May 2020 20:11:40 +0200
> 
> This time, instead of hitting RET, insert a pair of parentheses, and
> wait blink-matching-delay seconds until the opening parenthesis stops
> being highlighted.  Before and after your fix, the line-prefix
> disappears until I enter another command.

Fixed.