PURPOSE
Required fields are annoying, notably when dealing with tests or xml-based data
to create in concurrent modules. For example ModuleA adds a required field on
Model. ModuleB that does not depend on ModuleA tries to create a data of
Model. Currently it crashes as field is required but default is not provided if
ModuleA is not loaded in registry.
SPECIFICATIONS
Field activity_user_type on ir.actions.server model in mail is currently
required. This field is however not really required as its use is limited
to actions linked to activities. Remove the hard required and put it only
in views.
If no value is given due to some bad configuration no responsible will be
set.
Followup of odoo/odoo@7309981426
LINKS
Task ID-2367655
closesodoo/odoo#61769
Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com>