Use folly::atomic_compare_exchange_strong_explicit in futures
Use folly::atomic_compare_exchange_strong_explicit in futures

Summary: This helps avoid TSAN false positives.

Reviewed By: yfeldblum

Differential Revision: D20787056

fbshipit-source-id: e62537235e3ad876e3ec5266f9c449d0d8340330

facebook/folly,facebook/folly,facebook/folly,facebook/folly,facebook/folly