/**
   * {@inheritdoc}
   */
  public function addInstanceId($id, $configuration = NULL) {
    // @todo Open a core bug report, the parent class should take care of this..
    $this->instanceId = $id;
    $this->instanceIDs = array_filter($this->instanceIDs);

    parent::addInstanceId($id, $configuration);
  }
 /**
  * {@inheritdoc}
  */
 public function addInstanceId($id, $configuration = NULL)
 {
     $this->instanceId = $id;
     parent::addInstanceId($id, $configuration);
     if ($configuration !== NULL) {
         $this->setConfiguration($configuration);
     }
 }