pytorch

bc06eefe - [reland] Allow external CUDA streams to be set as current (#66324)

[reland] Allow external CUDA streams to be set as current (#66324) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/66324 Fixes https://github.com/pytorch/pytorch/issues/65822. Reland of https://github.com/pytorch/pytorch/pull/65914. ghstack-source-id: 140105651 Test Plan: Added tests Reviewed By: ngimel Differential Revision: D31506134 fbshipit-source-id: ff56203a120befdb282e974309478ac11aa56652