[FIX] ir_values: fallback when no condition

When searching for default values, if we set a condition (e.g. 'type=out_invoice'), fetch also the default values without any condition set. Thanks to the order by clause, the one with a condition have an higher priority than the one without and will not affect existing result.
This fixes default journal/currency on an invoice where the journal is retrieved in the onchange_company_id method (domain is forced). Without this patch only ir.values with a domain set will match, opw 610645
Merge branch '7.0' of https://github.com/odoo/odoo into 7.0-win32