bug#39706: 28.0.50; Search prefix nroff-mode

[Eli Zaretskii]

> From: Juri Linkov <juri@linkov.net>
> Cc: 39706@debbugs.gnu.org
> Date: Mon, 24 Feb 2020 01:02:46 +0200
> 
> Sorry for an unclear bug report.  What I described earlier is the case
> that exposed the problem in nroff-mode.  The problem itself is that
> the global search prefix keymap ‘M-s’ (search-map) is shadowed
> in nroff-mode by a keybinding that bounds the same key ‘M-s’
> in nroff-mode-map to ‘center-line’.
> 
> The solution already exists in text-mode from which nroff-mode inherits:
> text-mode binds ‘center-line’ to ‘M-o M-s’.  Thus just removing the
> keybinding ‘M-s’ from nroff-mode will make the search prefix ‘M-s’
> of search-map available in nroff-mode, whereas ‘M-o M-s’ will call 
> ‘center-line’ previously bound to ‘M-s’.

Thanks.  I'm okay with the change, but I think it should be called out
in NEWS as an incompatible change, with an explanation why we did
that.