Purpose: make some methods from mail.thread mixin private and update their
naming if necessary. Some methods prepare data for business flows and deal
with internal information. Public methods should either use of give some
access to those methods. Computation itself should be keps internal.
In this commit we put message_partner_info_from_emails as private. As it is
used in discuss JS we define a controller that controls access to this method.
It explicitly checks for related document access rule and rights before
calling the private method.
Some addons are updated accordingly to the method change.
Related to task ID 1911679
Linked to PR #29483
David Beguin
957c99abd5