if (NS_FAILED(scrollBox->GetChildBox(&scrolledBox)))
if (NS_FAILED(scrolledFrame->GetChildBox(&scrolledBox)))
static nsIBox* GetScrolledBox(nsBoxObject* aScrollBox) {  nsIFrame* frame = aScrollBox->GetFrame();  if (!frame)     return nsnull;  nsIScrollableFrame* scrollFrame;  if (NS_FAILED(CallQueryInterface(frame, &scrollFrame))) {    NS_WARNING("nsIScrollBoxObject attached to something that's not a scroll frame!");    return nsnull;  }  nsIFrame* scrolledFrame = scrollFrame->GetScrolledFrame();  if (!scrolledFrame)    return nsnull;  nsIBox* scrollBox;  if (NS_FAILED(CallQueryInterface(scrolledFrame, &scrollBox)))    return nsnull;  nsIBox* scrolledBox;  if (NS_FAILED(scrollBox->GetChildBox(&scrolledBox)))    return nsnull;  return scrolledBox;}