new function to get the *real* geometry position of a window, taken

new function to get the *real* geometry position of a window, taken

Sat Sep 25 23:33:55 1998  Tim Janik  <timj@gtk.org>

        * gdk/gdkwindow.c (gdk_window_get_root_origin): new function to get
        the *real* geometry position of a window, taken possible window
        manager offsets into account.
        this has been succesfully tested with fvwm, fvwm-2, bowman, olwm,
        olvwm, twm, ctwm, mlvwm, windowmaker and enlightenment.
        it does fail though for amiwm which adds windows to a pseudo root
        window, and for icewm by a small offset because it defines the
        geometry position whithin its border.

        * gtk/testgtk.c: added "saved position" test to figure how
        gdk_window_get_root_origin() interacts with window managers (repopup
        this window to figure ;).