pytorch

1659a267 - [PyTorchEdge] Export flatbuffers from _save_parameters() (#74579)

[PyTorchEdge] Export flatbuffers from _save_parameters() (#74579) Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/74579 Now that we can convert a module to a flatbuffer, update `_save_parameters()` to optionally write to that format. Also, rename the internal `ScriptModuleSerializer` class to `IValuePickler` to make it more clear that a) it's pickle-specific, and b) it serializes IValues, not Modules. ghstack-source-id: 152487889 Test Plan: New unit test shows that we can produce Flatbuffer-formatted output. ``` $ buck test //xplat/caffe2:test_lite_trainer //xplat/caffe2:test_lite_trainer_pickle_and_flatbuffer Building: finished in 0.5 sec (100%) 346/346 jobs, 0/346 updated Total time: 0.6 sec Testing: finished in 0.5 sec (26 PASS/0 FAIL) BUILD SUCCEEDED RESULTS FOR //xplat/caffe2:test_lite_trainer //xplat/caffe2:test_lite_trainer_pickle_and_flatbuffer PASS <100ms 13 Passed 0 Skipped 0 Failed //xplat/caffe2:test_lite_trainer PASS <100ms 13 Passed 0 Skipped 0 Failed //xplat/caffe2:test_lite_trainer_pickle_and_flatbuffer TESTS PASSED ``` A new test in later commit D34488913 tests the full round trip. Reviewed By: qihqi Differential Revision: D34408538 fbshipit-source-id: eea183c31b5e1b2b75a65f384d8a479223a4ae72 (cherry picked from commit de310a15422b65fb7e443f7005d287d9f5f586bc)