fix inliner bug (#25052)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/25052
Previously we would not inline nested functions, now we do.
Test Plan: Imported from OSS
Differential Revision: D16973848
Pulled By: suo
fbshipit-source-id: 94aa0b6f84a2577a663f4e219f930d2c6396d585
