Make InternalModel and Resnet work with rexportable flow (#106676)
Summary: Internal model and Resnet uses "re-export" flow now. Also did some refactoring to make the code little cleaner
Some changes for OSS:
1. Correctly use the "cached" fake tensors so that static symbols are still resolved to static
2. Change logic in PassBase to allocate static shapes for parameters
3. Add "is_torch_exported" tag to every node to make it survive during various graph transformations.
4. Added experimental wrapper API for quantization team to get pre_dispatch=True graph. Note that it doesn't actually do that right now. But we plan to switch soon.
Test Plan: CI
Differential Revision: D47890878
Pull Request resolved: https://github.com/pytorch/pytorch/pull/106676
Approved by: https://github.com/jerryzh168
