[FIX] account_asset: deferred revenue account

- Associate a product with a "Deferred Revenue Type"
- Create a customer invoice and add the product => the account of the
  deferred revenue is used.
- Create a SO with the same product, and generate the invoice => the
  account of the deferred revenue is NOT used.

opw-769254

addons/account_asset/models/account_invoice.py

@@ -107,4 +107,5 @@ class AccountInvoiceLine(models.Model):
                 self.asset_category_id = self.product_id.product_tmpl_id.deferred_revenue_category_id.id
             elif invoice.type == 'in_invoice':
                 self.asset_category_id = self.product_id.product_tmpl_id.asset_category_id.id
+            self.onchange_asset_category_id()
         super(AccountInvoiceLine, self)._set_additional_fields(invoice)