social/mail_tracking/views/res_partner_view.xml

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

<record model="ir.ui.view" id="view_partner_form">
    <field name="name">Partner Form with tracking emails</field>
    <field name="model">res.partner</field>
    <field name="inherit_id" ref="base.view_partner_form"/>
    <field name="arch" type="xml">
        <div name="button_box" position="inside">
            <button name="%(mail_tracking.action_view_mail_tracking_email)d"
                    context="{'search_default_recipient': email,
                              'default_recipient': email}"
                    type="action"
                    class="oe_stat_button oe_inline"
                    icon="fa-envelope-o"
                    attrs="{'invisible': [('email', '=', False)]}">
                <field name="tracking_emails_count"
                       widget="statinfo"
                       string="Tracking emails"/>
            </button>
        </div>
        <field name="email" position="after">
            <field name="email_score" widget="progressbar"
                   attrs="{'invisible': [('email', '=', False)]}"/>
        </field>
    </field>
</record>

</odoo>