bug#9361: 24.0.50; default value of `dired-do-chmod'

[Juri Linkov]

> I fixed up `dired-mark-read-string'; that's much safer, since there are
> only three callers to worry about.

Thank you, it's now safer.

There are still two problems:

In `dired-do-chmod':

>        (modes (dired-mark-read-string
>                "Change mode of %s to: "
>                ;; Insert initial input if there's only one file.
>                (unless (cadr files) default)
>                'chmod arg files default))

Please don't insert the default value as initial input.
Most of the time, users type short symbolic modes that
add/remove permissions on one user part such as "a=rw" or "go-w".
It would be annoying for them to delete initial input
before typing symbolic modes.

Another problem in `dired-mark-read-string':

> STANDARD-VALUE, if non-nil, should be a \"standard\" value or
> list of such values, available via history commands.

STANDARD-VALUE is non-standard terminology.  According to
`read-from-minibuffer' it's named DEFAULT-VALUE.