pytorch

c73cc92e - [FSDP] Use unflatten_parameter in _summon_full_parameters (#72467)

[FSDP] Use unflatten_parameter in _summon_full_parameters (#72467) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/72467 `_unflatten_params_as_views` does not (and cannot) delete `flat_param`. Using `_unflatten_params_as_views` to implement `_summon_full_parameters` will make the traverse of the full parameter failed -- will get the redundent flat_param. ghstack-source-id: 148959167 Test Plan: CI Reviewed By: rohan-varma Differential Revision: D33989893 fbshipit-source-id: 698c97766266be01d5b567b5d5f3b2fdbf24063d (cherry picked from commit f464c6f3909e408807594907896fd66fe639e3cb)