be returned after setting the'
                      + ' duration to zero');
}, 'Returns animations based on dynamic changes to individual'
   + ' animations\' duration');

test(t => {
  const div = createDiv(t);
  const animation = div.animate(null, 100 * MS_PER_SEC);

  animation.effect.updateTiming({ endDelay: -200 * MS_PER_SEC });
  assert_array_equals(div.getAnimations(), [],
                      'Animation should not be returned after setting a'
                      + ' negative end delay such that 