contract/contract_price_revision/views/contract_line.xml

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

    <record id="contract_line_tree_view" model="ir.ui.view">
        <field name="model">contract.line</field>
        <field name="inherit_id" ref="contract.contract_line_tree_view"/>
        <field name="arch" type="xml">
            <field name="last_date_invoiced" position="after">
                <field name="variation_percent" groups="base.group_no_one"/>
            </field>
        </field>
    </record>

    <record id="contract_line_form_view" model="ir.ui.view">
        <field name="model">contract.line</field>
        <field name="inherit_id" ref="contract.contract_line_form_view"/>
        <field name="arch" type="xml">
            <field name="discount" position="after">
                <field name="variation_percent"
                       groups="base.group_no_one"
                       attrs="{'invisible': [('predecessor_contract_line_id', '=', False)]}"/>
            </field>
        </field>
    </record>

</odoo>