protected function addJoin($type, $table, $join_condition, $langcode) {
$arguments = array();
if ($langcode) {
$placeholder = ':langcode' . $this->sqlQuery
->nextPlaceholder();
$join_condition .= ' AND %alias.langcode = ' . $placeholder;
$arguments[$placeholder] = $langcode;
}
return $this->sqlQuery
->addJoin($type, $table, NULL, $join_condition, $arguments);
}