bug#29872: 26.0.90; `man' output encoding, hyphen chars

[Drew Adams <drew.adams@oracle.com>]

> > I do `M-x shell' and see this in buffer `*shell*':
> >
> >  bash: cannot set terminal process group (-1): Inappropriate ioctl for
> >  device bash: no job control in this shell
> >
> > (Perhaps you have an idea about that?  If not, OK.)
> >
> > But doing what you said anyway (`man find > foo'), the output
> > is correct; the "hyphens" are actually hyphens:
> >
> >   name: HYPHEN
> >   general-category: Pd (Punctuation, Dash)
> >   decomposition: (8208) ('‐')
> 
> Then I think you will have to set up process-coding-system-alist such
> that it reads output from 'man' with utf-8 decoding.  I don't know
> what changed since Emacs 25, but if 'man' produces UTF-8 encoded
> hyphens by default, Emacs needs to be told about that.

I have no idea in what way to change
`process-coding-system-alist'.  The doc string and
(elisp) `Default Coding System' give me no hint that
I can recognize.

I don't even know whether it is the VAL (which is
`(raw-text-dos . raw-text-unix)') that is incorrect
or it is the PATTERN (which is "bash") that is
incorrect, or both.

And it is not even a user option.

_Someone_ should be able to tell "what changed
since Emacs 25", hopefully.  This is a (presumaby
incompatible) change in Emacs, not something a user
has provoked, AFAICS.

Suddenly something that (still) works in all prior
Emacs releases (as far back as Emacs 20, at least)
no longer works.