bug#38875: 26.2; auto-save-list-file-name still created when auto-save-default is nil

[João Guerra]

> I seem to be unable to reproduce this.  You are saying that just
> starting Emacs with the above settings causes the
> auto-save-list-file-name to appear in the file system?  It doesn't
> seem to happen here.

Just starting Emacs and waiting auto-save-timeout will create the
file. Setting auto-save-list-file-prefix to nil does make the file not
be created. I was setting auto-save-list-file-name to a directory
where it doesn't get in the way. Thanks!