bug#22557: 25.0.90; Saving a buffer under auto-revert turns off file notifications

[Eli Zaretskii <eliz@gnu.org>]

> From: Michael Albinus <michael.albinus@gmx.de>
> Cc: 22557@debbugs.gnu.org
> Date: Fri, 05 Feb 2016 13:24:01 +0100
> 
> > I don't understand the logic of this: at least with w32notify, when a
> > file is in auto-revert-mode, we watch the entire parent directory of
> > that file, so there's no need to send the 'stopped' event when the
> > file is renamed or deleted, only when the parent directory is deleted.
> 
> In `auto-revert-notify-add-watch', only the file named by
> `buffer-file-name' is watched. autorevert.el does not check, what the
> underlying library of filenotify.el is able to do, watching single files
> or whole directories.

I don't think the problem is in autorevert.el.  The problem is in
filenotify.el, which is where 'stopped' is generated.  Filenotify does
know what it watches.

> And as said, a renaming of a file should not turn file notifications
> off. I will try to fix this.

Neither should deleting a file, IMO.  Otherwise you will lose during
saving, since that's what Emacs does then.

> I really hate it that we have no ChangeLog anymore, maintained by the
> developers.

Maybe we should re-introduce them.  git-merge-changelog makes merging
them all but free of problems, so perhaps we are paying a price that's
too heavy for eliminating ChangeLog.