TensroIterator preserve format for binary, ternary operators.
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/28291
Test Plan: Imported from OSS
Differential Revision: D18044977
Pulled By: VitalyFedyunin
fbshipit-source-id: 793bab47d8cfc1b0d6229f1b0688352ee94c3e48
