bug#56682: Fix the long lines font locking related slowdowns

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: Stefan Monnier <monnier@iro.umontreal.ca>,  gerd.moellmann@gmail.com,
>   56682@debbugs.gnu.org,  gregory@heytings.org,  visuweshm@gmail.com
> Date: Sun, 24 Jul 2022 18:26:38 +0200
> 
> Random thought: Would it make sense to make `put-text-property' (and
> friends) try to ensure that `face' (and `font-lock-face'?) are towards
> the start of the plists?

The display code doesn't care only about 'face', it also cares for
'invisible' and 'display' properties.  And only one of them can be
"the first" ;-)