tionEquals(c1, 0, 100, 0, 50), "child 1 position ok");
          assert.isTrue(positionEquals(c2, 0, 100, 50, 100), "child 2 position ok");
          assert.isTrue(positionEquals(c3, 100, 200, 0, 50), "child 3 position ok");
          assert.isTrue(positionEquals(c4, 100, 200, 50, 100), "child 4 position ok");
          assert.isTrue(positionEquals(c5, 200, 300, 0, 50), "child 5 position ok");
        });

        test('layout-start-aligned', function() {
          container.classList.add('start-aligned');
