Revert D24665950: Create prototype for AST rewriter
Test Plan: revert-hammer
Differential Revision:
D24665950 (https://github.com/pytorch/pytorch/commit/54feb00bbde9f6220721259f4a352288ab610c03)
Original commit changeset: b72110436126
fbshipit-source-id: 961412df006acd33c91a745c809832d5c6494c76
