Revert D27404164: [PyTorch] Devirtualize is_contiguous
Test Plan: revert-hammer
Differential Revision:
D27404164 (https://github.com/pytorch/pytorch/commit/62aa9243687d842d1f5648b5f78dacc76bd6d813)
Original commit changeset: e1dce8c02100
fbshipit-source-id: 9caad109f371607479314501653c275ad95120b8
