This commit removes the legacy implementation of the form, kanban
and list views. It also removes the legacy view widget registry,
and all legacy widgets it contained. The legacy field registry
couldn't be removed yet as some fields are still used (e.g. in
client actions: FieldMany2One, FieldMany2ManyTags...), and
sometimes accessed from that registry (e.g. uom service). More
clean up will come later. Note that all tests using legacy views
have thus been removed, even though the tested feature might still
remain (e.g. FieldMany2One tests have been removed, but that field
is still there). However, those features are deprecated and
unlikely to evolve. They should be removed in the next saas, or the
one after.
Finally, this commit also removes the legacy view dialogs.
Task 3168640
Part-of: odoo/odoo#111809
Aaron Bohy
49297bc7bb