bug#35579: Add example of setting view-exit-action to a "function with one argument"

[martin rudalics]

> I finally found an example:
> (setq view-exit-action
>        (lambda (buffer)
>          (or (window-minibuffer-p (selected-window))
>              (when (eq (window-buffer) (get-buffer "*Help*"))
>                (if (one-window-p t)
>                    (delete-frame)
>                  (delete-window))))))
> So I think view-exit-action's docstring should have and example of what
> they are expecting.

To me this example is confusing since the BUFFER argument is nowhere
used within the lambda.

martin