server-tools/auto_backup/data/mail_message_subtype.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo noupdate="1">

    <record id="mail_message_subtype_success" model="mail.message.subtype">
        <field name="name">Backup Successful</field>
        <field name="description">Database backup succeeded.</field>
        <field name="res_model">db.backup</field>
        <field name="default" eval="False" />
    </record>

    <record id="mail_message_subtype_failure" model="mail.message.subtype">
        <field name="name">Backup Failed</field>
        <field name="description">Database backup failed.</field>
        <field name="res_model">db.backup</field>
        <field name="default" eval="True" />
    </record>

</odoo>