[FIX] core: mapped() does not prefetch as expected

Before this commit, calling `mapped()` on a relational field of a single
record inside a for loop does not correctly propagate the prefetch ids
from the bigger recordset down to the record inside the loop:

    [rec.line_ids.mapped('name') for rec in recs]

To be more precise, `recs` correctly propagates prefetching information
down to `rec.line_ids`, but method `mapped()` does not pass it along to
the record that triggers the prefetching.

This resulted in one query per record in `recs`, so if `recs` were a
1000 records recordset, at least 1000 queries would be necessary.

With this commit, the `mapped()` function correctly propagates the
`_prefetch_ids` of the larger recordset (`rec.line_ids`) so that the
prefetching works properly and the 1000 queries are brought down to 1.

This commit is a followup on #42611.

closes odoo/odoo#54565

X-original-commit: 0e97053fee36c0c76b70cb94be5340c3144b178b
Signed-off-by: Raphael Collet (rco) <rco@openerp.com>
Signed-off-by: Adrian Torres (adt) <adt@odoo.com>

0 files changed, 0 insertions, 0 deletions