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

[Eli Zaretskii]

> Date: Wed, 10 Aug 2022 14:54:51 +0300
> Cc: 56682@debbugs.gnu.org, Eli Zaretskii <eliz@gnu.org>,
>  monnier@iro.umontreal.ca
> From: Dmitry Gutov <dgutov@yandex.ru>
> 
> On 10.08.2022 13:55, Stephen Berman wrote:
> > Indeed, setting bidi-inhibit-bpa to t eliminates the delay.  Thanks.
> 
> Same here.
> 
> And the "faster computer" didn't help, apparently.
> 
> After flooring 'C-n', I even had to 'C-g' out of it for Emacs to regain 
> responsiveness, because waiting for a while didn't help.

That's strange, because on my "slower" computer I didn't see anything
like that.