function verifyItems(elementsFromContent, elementsFromUI) {
    for (const element of elementsFromUI) {
      expect(element.childNodes.length).toBeGreaterThan(0);
      const elementName = element.childNodes[0].textContent;
      expect(elementsFromContent.indexOf(elementName)).not.toBe(-1);
    }
  }
Make sure elements from content match their UI representation.
(The order doesn't matter).

@param {!Array<string>} elementsFromContent
@param {!Array<!HTMLElement>} elementsFromUI