Revert D31609714: Fix Dispatching not considering List[Optional[Tensor]] for dispatch
Test Plan: revert-hammer
Differential Revision:
D31609714 (https://github.com/pytorch/pytorch/commit/c581f56c74d3ce369885ee6221c486c39e7cb77f)
Original commit changeset: bb91cafd32fb
fbshipit-source-id: a04055e7af4bf8491b44bbc3e3bddc7831ab205e
