social/mass_mailing_sending_queue/data/ir_cron.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright 2016 Antonio Espinosa <antonio.espinosa@tecnativa.com>
     License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl). -->

<openerp>
<data noupdate="1">

<record id="cronjob" model="ir.cron">
    <field name="name">Mass mailing sending queue</field>
    <field name="interval_type">minutes</field>
    <field name="interval_number">1</field>
    <field name="numbercall">-1</field>
    <field name="model">mail.mass_mailing.sending</field>
    <field name="function">cron</field>
    <field name="nextcall">2016-01-01</field>
</record>

</data>
</openerp>