[FIX] account: avoid computing uom price if no product

Before this commit:

* Enable UOMs
* Create a new invoice and invoice line
* Set *only* the uom field of the invoice line
* Singleton expected error

This happens because the method _compute_price of `uom.uom` expects a
singleton, however since no product has been defined yet, it gets an
empty recordset which of course doesn't comply with self.ensure_one(),
raising a Singleton Error.

Functionally speaking, it makes sense to define a product before
choosing an uom, however a Singleton Error is an unexpected error, so
instead of doing that, we only calculate the price_unit if a product has
been chosen.

Fixes #28269

closes odoo/odoo#28278

0 files changed, 0 insertions, 0 deletions