This is a bunch of fixes (65 corner cases) for the search on
company-dependent fields:

Without a default value:
- `char` fields:
    - operators `not like`/`not ilike` don't return records with unset value
    - `(..., '=', False)` doesn't return records with unset value
    - `(..., '!=', '<string>')` doesn't return records with unset value
    - `(..., 'in', [..., False])` doesn't return records with unset value
    - `(..., 'not in', value)` without `False` inside `value` doesn't return records with unset value
- `date` and `datetime` fields:
    - `(..., '!=', <Date/datetime>)` doesn't return records with unset value
    - `(..., '=', False)` doesn't return records with unset value
- `many2one` fields:
    - operators `not like`/`not ilike` don't return records with unset value
    - `(..., 'in', [..., False])` doesn't return records with unset value
    - `(..., 'not in', value)` without `False` inside `value` doesn't return records with unset value
- `boolean` fields:
    - `(..., '=', False)` and `(..., '!=', True)` don't return records with unset and `False` values
- `integer`/`float` fields:
    - `(..., '!=', <number>)` doesn't return records with unset value

With a truthy default value:
- `many2one` fields:
    - operators `not like`/`not ilike` don't return records with unset value
    - `(..., '=', False)` returns the record with the default value (which isn't `False`)
- `boolean` fields:
    - `(..., '=', False)` doesn't return records with unset and `False` value
    - `(..., '!=', False)` returns records with unset and `False` value
- `integer`/`float` fields:
    - all `(..., operator, value)` which include value 0, return all records with unset value, even if the default value does not satisfy the domain

closes odoo/odoo#80082

Signed-off-by: Raphael Collet <rco@odoo.com>