Use correct company to get fiscal positions and properties
Ensure company used to fetch fiscal positions is always the correct one
when coming from a company restricted model (company_id required, or
related.required).
NB: if the company_id isn't defined, with_company doesn't change the
environment.
purchase: get_fiscal_position doesn't consider company_id ctxt key
others: properties were accessed with potentially the wrong company.
Victor Feyens
57b999d40a