Fix Dispatching not considering List[Optional[Tensor]] for dispatch (#66506)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/66506
Followup to https://github.com/pytorch/pytorch/pull/60787
It turns out that the original PR was wrong for unboxed kernels. We
recently ran into this in
https://github.com/facebookresearch/functorch/issues/124
For unboxed kernels, the correct type for a Tensor?[] argument is
actually `List<optional<Tensor>>`, not `ArrayRef<optional<Tensor>>`
Test Plan:
- assert that https://github.com/facebookresearch/functorch/issues/124
actually works
Reviewed By: bdhirsh
Differential Revision: D31609714
Pulled By: zou3519
fbshipit-source-id: bb91cafd32fb3c1b7d1e4f966b46b5d973b50df2
