DatabaseStorage::rename

public DatabaseStorage::rename($name, $new_name)

public function rename($name, $new_name) {
  $options = array('return' => Database::RETURN_AFFECTED) + $this->options;
  return (bool) $this->connection->update($this->table, $options)
    ->fields(array('name' => $new_name))
    ->condition('name', $name)
    ->condition('collection', $this->collection)
    ->execute();
}