private boolean useUnitedRoundedSelection() {
		return selectionArc > 0 &&
			(selectionInsets == null || (selectionInsets.top == 0 && selectionInsets.bottom == 0));
	}
Similar to super.paintRow(), but supports wide selection and uses
inactive selection background/foreground if tree is not focused.
flatlaf-core/src/main/java/com/formdev/flatlaf/ui/FlatTreeUI.java