Nit: Use `isEmpty` instead of checking for size == 0
Nit: Use `isEmpty` instead of checking for size == 0

Summary: My Java is a bit rusty :|

Reviewed By: stepancheg

shipit-source-id: 56d38717b7

Addepar/buck,zpao/buck,nguyentruongtho/buck,JoelMarcey/buck,facebook/buck,facebook/buck,nguyentruongtho/buck,zpao/buck,nguyentruongtho/buck,nguyentruongtho/buck,Addepar/buck,JoelMarcey/buck,Addepar/buck,zpao/buck,kageiit/buck,Addepar/buck,facebook/buck,facebook/buck,Addepar/buck,Addepar/buck,Addepar/buck,JoelMarcey/buck,JoelMarcey/buck,Addepar/buck,JoelMarcey/buck,facebook/buck,kageiit/buck,facebook/buck,JoelMarcey/buck,zpao/buck,JoelMarcey/buck,zpao/buck,JoelMarcey/buck,zpao/buck,JoelMarcey/buck,nguyentruongtho/buck,JoelMarcey/buck,kageiit/buck,nguyentruongtho/buck,kageiit/buck,Addepar/buck,kageiit/buck,Addepar/buck,JoelMarcey/buck,Addepar/buck,Addepar/buck,kageiit/buck,zpao/buck,nguyentruongtho/buck,kageiit/buck,JoelMarcey/buck,JoelMarcey/buck,Addepar/buck,facebook/buck