Support parent context in left part of domain eval expression in view

[trinhanhngoc]

https://github.com/odoo/odoo/blob/ec929f787f629940cd38a4ed25e5012335e2483d/addons/sale/views/sale_order_views.xml#L494

[('parent.state', 'not in', ['draft', 'sent', 'sale'])]: parent is a reference to the record context of the parent view.

Ref:

1. https://github.com/odoo/odoo/blob/ec929f787f629940cd38a4ed25e5012335e2483d/addons/web/static/src/views/fields/field.js#L132
2. https://github.com/odoo/odoo/blob/ec929f787f629940cd38a4ed25e5012335e2483d/addons/web/static/src/core/domain.js#L203
3. https://github.com/odoo/odoo/blob/ec929f787f629940cd38a4ed25e5012335e2483d/addons/web/static/src/views/relational_model.js#L469