if (NS_SUCCEEDED(view->QueryInterface(kScrollViewIID, (void**)&scrollingView))) {
if (NS_SUCCEEDED(view->QueryInterface(NS_GET_IID(nsIScrollableView), (void**)&scrollingView))) {
nsScrollBoxObject::GetScrollableView(){  // get the frame.  nsIFrame* frame = GetFrame();  if (!frame)     return nsnull;    nsCOMPtr<nsIPresContext> context;  mPresShell->GetPresContext(getter_AddRefs(context));  nsIView* view;  frame->GetView(context, &view);  nsIScrollableView* scrollingView = nsnull;  if (NS_SUCCEEDED(view->QueryInterface(kScrollViewIID, (void**)&scrollingView))) {      return scrollingView;  }  return nsnull;}