pytorch

28166395 - [Opt Overlap] Create Optimizer Hook State directly from functional optim (#71602)

[Opt Overlap] Create Optimizer Hook State directly from functional optim (#71602) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/71602 The design in https://github.com/pytorch/pytorch/issues/67570 requires `_OptimizerHookState` to be created directly from a functional optimizer. Add support and tests for this. Also refactor a few tests. ghstack-source-id: 147577175 Test Plan: CI Reviewed By: cbalioglu Differential Revision: D33687477 fbshipit-source-id: f3c789aa77773f918e01a8d0cf08739b2edf07b3 (cherry picked from commit 4851e1c6d4a200d6efcc8354c98936ab4044f761)