Making empty vector an error
Making empty vector an error

Reviewed By: akotulski

Differential Revision: D3434750

fbshipit-source-id: d60275a

ropas/infer,facebook/infer,ryoon/infer,facebook/infer,ropas/infer,jvillard/infer,xennygrimmato/infer,jsachs/infer,kageiit/infer,jvillard/infer,kageiit/infer,xennygrimmato/infer,jvillard/infer,ryoon/infer,ryoon/infer,blzq/infer,kageiit/infer,ropas/infer,jsachs/infer,jsachs/infer,facebook/infer,facebook/infer,jsachs/infer,kageiit/infer,jvillard/infer,ropas/infer,xennygrimmato/infer,kageiit/infer,jvillard/infer,facebook/infer,xennygrimmato/infer,xennygrimmato/infer,xennygrimmato/infer,jsachs/infer,blzq/infer,kageiit/infer,blzq/infer,kageiit/infer,ryoon/infer,ropas/infer,jsachs/infer,blzq/infer,blzq/infer,ryoon/infer,ryoon/infer,jvillard/infer,jvillard/infer,facebook/infer,xennygrimmato/infer,blzq/infer,facebook/infer,ropas/infer