Store an actual value in atomic<bool>
Store an actual value in atomic<bool>

Summary:
The downside of implicit conversions is that things like this go unnoticed. Happily though, MSVC generates a warning for this.
The values were being implicitly converted to `true`, so they still worked, but definitely not as intended.

Reviewed By: yfeldblum, lbrandy

Differential Revision: D4444179

fbshipit-source-id: 5de5f7c228a3138f26060fd1d4aeb158c6a87ed3

facebook/wangle,facebook/wangle,facebook/wangle