[FIX] core: fix filtered_domain for hierarchical terms

The method filtered_domain() is broken for domains with hierarchical
terms ('child_of'/'parent_of').

To see *one* of the ways the implementation is broken, let `A` be a
model with `parent_id` pointing to `A`, and `a1` a record of model `A`
without parent (`a1.parent_id` is `False`), then this fails:

    assert a1 in a1.filtered_domain([("parent_id", "child_of", a1.id)])

The reason it fails is that on
https://github.com/odoo/odoo/blob/f5519586d214a9b34ad24683a7f97c47802a3bad/odoo/models.py#L5377-L5380
`data` is empty since `a1` has no parent, thus
https://github.com/odoo/odoo/blob/f5519586d214a9b34ad24683a7f97c47802a3bad/odoo/models.py#L5403-L5404


fails, therefore the result of `filtered_domain` is empty.

Note: the implementation of the hierarchical operators is full of quirks
that are hard to emulate otherwise than by reusing the original code.
As a consequence, the current implementation may be broken in more than
one way.

Let's see another way the implementation is broken: let `B` be a model
without a `parent_id` field and with a `friend_id` field pointing
to `B`, and let `b1` be a record of model `B`.  Then

    b1.filtered_domain([("friend_id", "child_of", b1.id)])

throws an exception of the form shown below:

    ValueError: Invalid field 'parent_id' in leaf "<osv.ExtendedLeaf: ('parent_id', 'child_of', 1) ...

Meanwhile the following code is still valid and returs b1:

    B.search([("friend_id", "child_of", b1.id)])

closes odoo/odoo#71237

X-original-commit: e7a5ba95
Signed-off-by: Raphael Collet (rco) <rco@openerp.com>