cap the maximum depth of bailout chains at 1 (#32073)
Summary:
This is another implementation of the maximum bailout depth.
The first version was implemented in https://github.com/pytorch/pytorch/pull/31521
This one has advantages that
* the bailout depth only exists in `CodeImpl` which seems to be an appropriate place to keep it in.
* threading many objects is reduced to threading through CodeImpl and getPlanFor
Pull Request resolved: https://github.com/pytorch/pytorch/pull/32073
Differential Revision: D19443432
Pulled By: Krovatkin
fbshipit-source-id: 898384bb2308a1532a50a33d9e05cfca504711e6
