Refactor Random Number Generators in ATen (#21555)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/21555
ghimport-source-id: dd900a8c3e1ef9ef1e011b8bb5476626d18cc462
Test Plan: Imported from OSS
Differential Revision: D15875780
Pulled By: ezyang
fbshipit-source-id: 6e04e90af62ab9c9593d74f344a3a084aaaf6f43
