[IMP] web: customize the save/close button of a `FormViewDialog`
[IMP] web: customize the save/close button of a `FormViewDialog`

Purpose
=======
In Social, we want to be able to change the "Save" button into a "Add"
button when we add a new stream. For that purpose, we need to be able to
customize the text of the `FormViewDialog` buttons.

Task-2234580
See odoo/enterprise/pull/9933

closes odoo/odoo#49622

Related: odoo/enterprise#9933
Signed-off-by: Thibault Delavallee (tde) <2d325771bb6e8870d87f0f3f7b45589a8338e550@openerp.com>

ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo,ygol/odoo