Should correctly handle / fallback to regular code when processing
non-stored partners.
Perf difference according to cprofile on my machine:
original python:
ncalls tottime percall cumtime percall filename:lineno(function)
1 0.134 0.134 205.380 205.380 res_partner.py:277(_compute_commercial_partner)
SQLized
1 0.118 0.118 67.239 67.239 res_partner.py:280(_compute_commercial_partner)
most of the time leftover seems to be in modified_draft