Before this commit, when a record from a relational model would start to
load, it would empty its `data` object. The issue is that a rendering
process can be initiated right after a record started loading. In kanban
views, this causes a crash since all records are always assumed to
contain values in their data objects.
This commit takes care to only clean strictly unwanted data when loading
a record instead of removing all the values, ensuring that records
always contain data.
closesodoo/odoo#100414
Signed-off-by: Aaron Bohy (aab) <aab@odoo.com>