Implement dropout with replacement for id list features. (#22880)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/22880
Implement sparse dropout with replacement value.
Reviewed By: xianjiec
Differential Revision: D16267012
fbshipit-source-id: 8c4878230f61bb3ac333291e2c6aaf2fbdc5f9ce
