private void paintWideSelection( Graphics g, Rectangle bounds, int row ) {
		float arcTop, arcBottom;
		arcTop = arcBottom = UIScale.scale( selectionArc / 2f );

		if( useUnitedRoundedSelection() ) {
			if( row > 0 && tree.isRowSelected( row - 1 ) )
				arcTop = 0;
			if( row < tree.getRowCount() - 1 && tree.isRowSelected( row + 1 ) )
				arcBottom = 0;
		}

		FlatUIUtils.paintSelection( (Graphics2D) g, 0, bounds.y, tree.getWidth(), bounds.height,
			UIScale.scale( selectionInsets ), arcTop, arcTop, arcBottom, arcBottom, 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