testPositioningBelowAnchor() {
    const node = dom.getElement('demoMenuButton');
    menuButton.decorate(node);

    // Show the menu.
    menuButton.setAlignMenuToStart(true);  // Should get overridden below
    menuButton.setScrollOnOverflow(true);  // Should get overridden below

    const position = new MenuAnchoredPosition(
        menuButton.getElement(), Corner.BOTTOM_START,
        /* opt_adjust */ false, /* opt_resize */ false);
    menuButton.setMenuPosition(position);
    menuButton.setOpen(true);

    // Confirm the menu position
    const buttonBounds = style.getBounds(node);
    const menuNode = menuButton.getMenu().getElement();
    const menuBounds = style.getBounds(menuNode);

    expectedFailures.expectFailureFor(isWinSafariBefore5());
    try {
      assertRoughlyEquals(
          menuBounds.top, buttonBounds.top + buttonBounds.height, 3);
      assertRoughlyEquals(menuBounds.left, buttonBounds.left, 3);
    } catch (e) {
      expectedFailures.handleException(e);
    }
    // For this test to be valid, the node must have non-trival height.
    assertRoughlyEquals(node.offsetHeight, 19, 3);
  }
Test forced positioning below the button.
     @suppress {strictMissingProperties} suppression added to enable type
     checking