eZ\Publish\Core\Search\Common\Slot\MoveUserGroup::receive PHP Method

    public function receive(Signal $signal)
    {
        if (!$signal instanceof Signal\UserService\MoveUserGroupSignal) {
            return;
        }
        $userGroupContentInfo = $this->persistenceHandler->contentHandler()->loadContentInfo($signal->userGroupId);
        // Moving UserGroup moves its main Location, so we only need to
        // (re)index main Location's subtree
        $this->indexSubtree($userGroupContentInfo->mainLocationId);
    }