ing.html#tables-2
 * We can't check for these values directly, because they may be
 * serialized slightly differently when read from the computed style.
 * So, for each property here, we apply it to a "reference" div and then
 * read back the computed value, and we validate that a table element
 * has that same computed value by default. */
const defaultTablePropVals = {
  'display':         'table',
  'box-sizing':      'border-box',
  'border-spacing':  '2px',
  'border-collapse': 'separate',
  'text-inde