bug#64697: 29.0.92: cannot paste NUL on macOS (regression from Emacs 28)

[Eli Zaretskii]

> From: Mattias Engdegård <mattias.engdegard@gmail.com>
> Date: Tue, 18 Jul 2023 14:00:49 +0200
> Cc: 64697@debbugs.gnu.org,
>  alan@idiocy.org
> 
> 18 juli 2023 kl. 13.28 skrev Eli Zaretskii <eliz@gnu.org>:
> 
> > do we want a unibyte string
> > here or a multibyte string?
> >  We should try to call either
> > make_unibyte_string or make_multibyte_string accordingly, because
> > make_string has its own ideas about which one to produce.
> 
> That is more than I expected to change in emacs-29, but we could do that too 
> if you like.

Let's install your change on emacs-29, and do the rest (if needed) on
master.

> Since the input is UTF-8 the result, with the patch, will always be either a 
> multibyte string or a unibyte ASCII string. Always making a multibyte string 
> would also do and be marginally faster, but not more correct in any 
> meaningful way.

OK, but please add a comment there with the above rationale.

Thanks.