bug#5616: 23.1.92; `delete-frame' deletes the last frame when emacsclient runs

[Chong Yidong]

> when I run `emacs --daemon -Q' and `emacsclient -nc', then if I try `M-x
> delete-frame', emacsclient seems will delete last remaining frame
> without check or remind.
>
> I think it should be mentioned in the manuals, but all I got said emacs
> will not to delete the last frame, even you try `M-x delete-frame'.
>
> So I think at least there is a doc bug, and manuals should mention about
> that.

Thanks, I have made a note of this in the manual.