inconsistent handling of stderr in notmuch-emacs

[Tomi Ollila]

On Fri, Mar 15 2019, David Bremner wrote:

> Rob noticed that generating extra output on stderr from the notmuch cli
> breaks some things in notmuch-emacs (in his case this was from a wrapper
> script).
>
> notmuch-search seems fairly robust at this point, but at least
> notmuch-hello and notmuch-mua-mail get confused by the extra
> output. I guess this is because of code calling #'call-process without
> specifying something to do with stderr.
>
> I don't know how often this is problem, but I guess it would be nice to
> eventually only call notmuch using make-process (for recent enough
> emacs). This allows cleaner handling of stderr.

for Older emacses the following code snippet could be utilized 
(originally a13b38824 (Austin Clements 2013-05-31)):

    (proc (apply #'start-process name buffer
                 "/bin/sh" "-c" 
                 "exec 2>\"$1\"; shift; exec \"$0\" \"$@\""
                 command err-file args))

But if we dropped support for emacs 24 (NEWS.25 mentioned make-process)
then we could use make-process everywhere :D

Tomi