Remove state from schema and calling API (#16180)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/16180
Only the kernel knows about its state, the caller doesn't see it anymore.
Reviewed By: ezyang
Differential Revision: D13744071
fbshipit-source-id: cb00ff1a881508c1b36ac4123bee1f68ca02ca9c
