Consider models `M` and `L`, with a one2many field `M.l_ids` with
inverse `L.m_id`. Consider also a computed field `L.foo` that depends
on `L.m_id`.
The field `L.foo` is not computed correctly by `onchange` on a new line
in the form view of `M`: its value is forced to `False` because it has
no default, and is not recomputed by `onchange` since the field `L.m_id`
is never triggered an `onchange`.
Modify the method `onchange` to not force fields without a default to
`False`, and return all fields.
Raphael Collet
3e91fa1dbf