/**
  * Returns a list of conversation labels for given user id.
  * 
  * @param	integer		$userID
  * @return	\wcf\data\conversation\label\ConversationLabelList
  */
 public static function getLabelsByUser($userID = null)
 {
     if ($userID === null) {
         $userID = WCF::getUser()->userID;
     }
     $labelList = new ConversationLabelList();
     $labelList->getConditionBuilder()->add("conversation_label.userID = ?", array($userID));
     $labelList->readObjects();
     return $labelList;
 }