/**
  * Given a local time stamp, convert the time stamp to UTC based on a timezone adjusted time stamp.
  * The time zone is based on the current user's time zone.
  */
 public function convertFromLocalTimeStampForCurrentUser($utcTimeStamp)
 {
     assert('is_int($utcTimeStamp)');
     $timeZone = $this->getForCurrentUser();
     return DateTimeUtil::convertFromLocalUnixStampByTimeZoneToUtcUnixStamp($utcTimeStamp, $timeZone);
 }