pos/pos_dynamic_price/view/pos_dynamic_price_template.xml

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