Fix atomic_vector_test
Fix atomic_vector_test

Summary:
The "undefined symbol" errors are all magically fixed (they were likely broken
due to some of my LAR diffs last week) but atomic_vector_test had a genuine
failure.

Test Plan: ran it

Reviewed By: ntv@fb.com

Subscribers: ntv, fjargsto, pamelavagata, jhj, lesha

FB internal diff: D1552980

szagoruyko/fblualib,soumith/fblualib,soumith/fblualib,raphaelamorim/fblualib,raphaelamorim/fblualib,facebook/fblualib,facebook/fblualib,szagoruyko/fblualib