This PR implements CRUD for view filter groups with the new logic as
already done for view filters and view sorts.
It also completely removes the old combined view filter group states and
usage.
This PR is quite big but the impact is limited since it only changes
advanced filters module, which is under feature flag at the moment, and
it is already in a broken state so unusable, even if someone activates
the feature flag.
aba20dae11