[hack] parenthesize expressions in macros
[hack] parenthesize expressions in macros

Summary:
paranoia, parenthesize expressions in macros so we don't get bitten by
precedence issues

Reviewed By: alexchow

Differential Revision: D7730960

fbshipit-source-id: 3d77f13fe1abcaf0cf7db33a0a6afb2f4b19d9ab

facebook/flow,AgentME/flow,gabelevi/flow,facebook/flow,JonathanUsername/flow,AgentME/flow,claudiopro/flow,facebook/flow,mroch/flow,samwgoldman/flow,nmote/flow,jamesgpearce/flow,mroch/flow,claudiopro/flow,jamesgpearce/flow,jamesgpearce/flow,facebook/flow,samwgoldman/flow,facebook/flow,JonathanUsername/flow,samwgoldman/flow,popham/flow,JonathanUsername/flow,popham/flow,popham/flow,gabelevi/flow,facebook/flow,mroch/flow,nmote/flow,nmote/flow,jamesgpearce/flow,gabelevi/flow,gabelevi/flow,popham/flow,facebook/flow,popham/flow,popham/flow,samwgoldman/flow,nmote/flow,jamesgpearce/flow,gabelevi/flow,gabelevi/flow,AgentME/flow,mroch/flow,AgentME/flow,jamesgpearce/flow,AgentME/flow,samwgoldman/flow,JonathanUsername/flow,popham/flow,nmote/flow,samwgoldman/flow,claudiopro/flow,claudiopro/flow,mroch/flow,claudiopro/flow,nmote/flow,mroch/flow,jamesgpearce/flow,JonathanUsername/flow,mroch/flow,JonathanUsername/flow,JonathanUsername/flow,samwgoldman/flow,gabelevi/flow,nmote/flow