function drawTargets(targets, multiplier) {
  const colors = ['green', 'blue', 'red', 'lime', 'pink', 'silver', 'orange'];
  const cont = document.getElementById('cont');
  cont.innerHTML = '';
  for (let i = 0; i < targets.length; i++) {
    /**
     * @suppress {strictMissingProperties} suppression added to enable type
     * checking
     */
    const box = targets[i].box_;
    const el = dom.createElement(TagName.DIV);
    el.style.top = (box.top * multiplier) + 'px';
    el.style.left = (box.left * multiplier) + 'px';
    el.style.width = ((box.right - box.left) * multiplier) + 'px';
    el.style.height = ((box.bottom - box.top) * multiplier) + 'px';
    el.style.backgroundColor = colors[i];
    cont.appendChild(el);
  }
}
Helper function for manual debugging.
@param {!Array<*>} targets
@param {number} multiplier