Right now, when a port has delegatesScrolling set to FALSE, and constrainsScrollingToContentEdge set to TRUE (i.e. it acceptes over scrolled position), calling ScrollView::setScrollPosition with an overscrolled position still gets the position clamped to the content size edges. We could relax ::adjustScrollPositionWithinRange in that sense.
*** This bug has been marked as a duplicate of bug 84178 ***