don't propagate exposes to NULL child.

don't propagate exposes to NULL child.

Fri May 11 02:53:57 2001  Tim Janik  <timj@gtk.org>

        * gtk/gtktogglebutton.c (gtk_toggle_button_expose): don't
        propagate exposes to NULL child.

        * gtk/gtkscrolledwindow.c (gtk_scrolled_window_adjustment_changed): guard
        against not having one of the scrollbars.

        * gtk/gtklabel.c (gtk_label_setup_mnemonic): clean up after us,
        we don't keep a mnemonic window if we have no mnemonic installed.