pos/pos_pricelist/views/pos_pricelist_template.xml

<openerp>
    <data>
        <template id="pos_pricelist_assets_backend"
                  name="pos_pricelist_assets_backend"
                  inherit_id="point_of_sale.assets_backend">
            <xpath expr="." position="inside">
                <script src="/pos_pricelist/static/src/js/db.js"
                        type="text/javascript"></script>
                <script src="/pos_pricelist/static/src/js/models.js"
                        type="text/javascript"></script>
                <script src="/pos_pricelist/static/src/js/widgets.js"
                        type="text/javascript"></script>
                <script src="/pos_pricelist/static/src/js/screens.js"
                        type="text/javascript"></script>
                <script src="/pos_pricelist/static/src/js/tests.js"
                        type="text/javascript"></script>
                <script src="/pos_pricelist/static/src/js/main.js"
                        type="text/javascript"></script>
            </xpath>
        </template>

        <template id="pos_pricelist_assets" name="pos_pricelist_css" inherit_id="point_of_sale.index">
            <xpath expr="//script[@id='loading-script']" position="before">
                <link rel="stylesheet" href="/pos_pricelist/static/src/css/style.css"/>
            </xpath>
        </template>

    </data>
</openerp>