split onnx passes (#22413)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/22413
_jit_pass_erase_number_types invalidates the jit graph but parts of _jit_pass_onnx rely on having a valid jit graph.
This splits _jit_pass_onnx into _jit_pass_onnx_remove_print and _jit_pass_onnx_preprocess_caffe2 (which rely on the valid jit graph), runs these before _jit_pass_erase_number_types,
and then runs the rest of _jit_pass_onnx after _jit_pass_erase_number_types
Reviewed By: houseroad
Differential Revision: D16079890
fbshipit-source-id: ae68b87dced077f76cbf1335ef3bf89984413224
