Propogate dynamo shape_env to make_fx (#96437)
Currently, when we use assume_static_by_default flag, dynamo won't produce any symbols for input tensors. But when we pass the dynamo generated graph onto make_fx via torchdynamo.export(aten_graph=True), there is no way to pass this flag. We enable this by directly passing the fake tensors dynamo used to make_fx and call make_fx with "real" mode with fake tensors from dynamo.
Note that this is modified version of (https://github.com/pytorch/pytorch/pull/96143)
Differential Revision: [D44561753](https://our.internmc.facebook.com/intern/diff/D44561753)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/96437
Approved by: https://github.com/jansel, https://github.com/ezyang