Fix build on windows
Fix build on windows

Summary: Fix for build on windows

Reviewed By: mweststrate

Differential Revision: D20601309

fbshipit-source-id: 9845964513d7904f58e3511b1c4daa8716f7b054

facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper,facebook/flipper