Bug 283631 [CSS] ETabFolder in CTabFolder mode top/bottom keylines differ
bundles/org.eclipse.e4.ui.widgets/src/org/eclipse/e4/ui/widgets/ETabFolder.java
left = E_TOP_LEFT_CORNER_BORDERLESS;
		right = E_TOP_RIGHT_CORNER_BORDERLESS;
	}
	
	shape = new int[left.length + right.length + 4];
	int index = 0;
	shape[index++] = x;
	shape[index++] = y + height + highlight_header + 1;
	for (int i = 0; i < left.length / 2; i++) {
		shape[index++] = x + left[2 * i];
		shape[index++] = y + left[2 * i + 1];
	}
	for (int i = 0; i < right.length / 2; i++) {
		shape[index++] = x + width + right[2 * i];
		shape[index++] = y + right[2 * i + 1];
	}
	shape[index++] = x + width;
	shape[index++] = y + height + highlight_header + 1;
	
	boolean bkSelected = single && selectedIndex != -1;
	drawBackground(gc, shape, bkSelected);
	
	Region r = new Region();
	r.add(new Rectangle(x, y, width + 1, height + 1));
	r.subtract(shape);
	gc.setBackground(getParent().getBackground());
	fillRegion(gc, r);
	r.dispose();
	
	for (int i = 0; i < items.length; i++) {