/**
  * Add a selection to the set of selected options in a multi-select
  * element using an option locator.
  *
  * @param  string  $locator
  * @return string
  * @access public
  */
 public function addSelection($locator, $optionLocator)
 {
     return $this->selenium->addSelection($locator, $optionLocator);
 }