bug#33263: 27.0.50; Tidying up Gnus modes

[Noam Postavsky]

Eric Abrahamsen <eric@ericabrahamsen.net> writes:

> +(defvar gnus-browse-mode-map (make-keymap))
>  
>  (unless gnus-browse-mode-map
> -  (setq gnus-browse-mode-map (make-keymap))
> +  (defvar gnus-browse-mode-map (make-keymap))

This doesn't look right.

> -(defun gnus-summary-mode (&optional group)
> +(define-derived-mode gnus-summary-mode gnus-mode "Summary"
>    "Major mode for reading articles.

> -      (gnus-summary-mode group)
> +      (setq gnus-newsgroup-name group)
> +      (gnus-summary-mode)
>        (when (gnus-group-quit-config group)

Where does GROUP come from now?