LatchRect
virtual BRect LatchRect(BRect itemRect, int32 level) const;
BRect latchRect = LatchRect(BRect(0, 0, item->Width(), item->Height()),
&& LatchRect(ItemFrame(index), item->fLevel).Contains(where)) {
Invalidate(LatchRect(ItemFrame(index), superItem->OutlineLevel()));
Invalidate(LatchRect(ItemFrame(IndexOf(super)),
BRect latchRect(LatchRect(itemRect, level));
itemRect.left += LatchRect(itemRect, item->fLevel).right;