bug#29080: 25.3; dired-x does not update `shell-command-history'

[Eli Zaretskii]

> From: "Matz, Daniel A. (JSC-EG511)" <daniel.a.matz@nasa.gov>
> Date: Tue, 31 Oct 2017 15:39:55 +0000
> 
> After starting emacs with -Q, if I open a dired buffer, use M-! to run a 
> shell command, then use ! to run a shell command on a dired entry, and then 
> look at the contents of `shell-command-history’, I’ll see both commands.  But 
> then if I (require 'dired-x), run a shell command with M-!, and then another 
> with !, the command I ran with ! on a dired entry does not show up in 
> `shell-command-history’.

It's a feature: after loading dired-x, M-! runs a different command
(dired-smart-shell-command), which stores its history in a different
variable (dired-shell-command-history).