[PyTorch] Devirtualize TensorImpl::sizes() with macro (#50176)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/50176
UndefinedTensorImpl was the only type that overrode this, and IIUC we don't need to do it.
ghstack-source-id: 119609531
Test Plan: CI, internal benchmarks
Reviewed By: ezyang
Differential Revision: D25817370
fbshipit-source-id: 985a99dcea2e0daee3ca3fc315445b978f3bf680
