Add simple unit tests to validate all configs
Add simple unit tests to validate all configs

Summary: Add simple unit tests to validate all configs: as demonstrated by the previous diff, this can not hurt :)

Reviewed By: vkhalidov

Differential Revision: D20491383

fbshipit-source-id: 1c7b82dfbf9cde43d38ece64a5fb1692d1c03a9b

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