* gtk/gtkscrolledwindow.c (SCROLLBAR_SPACING): this macro computes
the spacing from klass->scrollbar_spacing now. adapted all functions
that used this macro (based on a patch from Patrice Fortier).
* gtk/gtkscrolledwindow.h (struct _GtkScrolledWindowClass): added
scrollbar_spacing to substitute a define (patch from Patrice Fortier).
-timj