Fix return type

     * Creates a group with data taken from the constructor.

     * @return number of affected rows

     * @throws RemoteException on contact provider errors

     * @throws ContactsStorageException when the group can't be added

     */

    fun add(): Uri {

        val values = contentValues()

        values.put(Groups.SHOULD_SYNC, 1)

        // read-only: values.put(Groups.GROUP_VISIBLE, 1);

        val uri = addressBook.provider!!.insert(addressBook.syncAdapterURI(Groups.CONTENT_URI), values)

                ?: throw ContactsStorageException("Empty result from content provider when adding group")

        id = ContentUris.parseId(uri)

        return uri

	}