bug#59935: 29.0.60; project-list-buffers is slow

[Eli Zaretskii]

> From: Juri Linkov <juri@linkov.net>
> Cc: dgutov@yandex.ru,  59935@debbugs.gnu.org
> Date: Sun, 11 Dec 2022 19:56:24 +0200
> 
> >> > Do you have the time to finish the fix yourself? It was your feature, 
> >> > after
> >> > all.
> >> 
> >> Here is a complete patch tested for all possible cases:
> >> - emacs 28/29
> >> - with/without file arg
> >> - with/without reverting
> >
> > Thanks, but I hope you don't intend to ask to install this on the
> > release branch.  And changing back the signature of
> > list-buffers-noselect is extremely problematic, even though we changed
> > it only for Emacs 29.
> >
> > Please try to find a safer, more compatible solution.
> 
> This is the safest solution for the emacs-29 branch.

I don't see how it could be the safest.  For example, an almost
identical changeset that doesn't change the signature of
list-buffers-noselect is definitely safer.  And likewise with the
change of list-buffers--refresh -- why do we have to do that?