Element matchingTarget

A pointer to the element whose CSS selector matched within which an event was fired. If this Event was not associated with any Event delegation, accessing this value will throw an UnsupportedError.

Source 

Element get matchingTarget {
  if (_selector == null) {
    throw new UnsupportedError('Cannot call matchingTarget if this Event did'
        ' not arise as a result of event delegation.');
  }
  Element currentTarget = this.currentTarget;
  Element target = this.target;
  var matchedTarget;
  do {
    if (target.matches(_selector)) return target;
    target = target.parent;
  } while (target != null && target != currentTarget.parent);
  throw new StateError('No selector matched for populating matchedTarget.');
}