Backend file should finish creating file before map it.
Backend file should finish creating file before map it.


Former-commit-id: 0698eff4d6b35da1572aeadce08128bd91624607
seojungmin/peloton,jessesleeping/iso_peloton,phisiart/peloton-p3,malin1993ml/peloton,apavlo/peloton,vittvolt/peloton,prashasthip/peloton,vittvolt/peloton,vittvolt/15721-peloton,jessesleeping/iso_peloton,cmu-db/peloton,ShuxinLin/peloton,apavlo/peloton,seojungmin/peloton,seojungmin/peloton,jessesleeping/iso_peloton,yingjunwu/peloton,prashasthip/peloton,yingjunwu/peloton,AngLi-Leon/peloton,jessesleeping/iso_peloton,haojin2/peloton,wangziqi2016/peloton,apavlo/peloton,eric-haibin-lin/peloton-1,PauloAmora/peloton,PauloAmora/peloton,wangziqi2016/peloton,vittvolt/15721-peloton,phisiart/peloton-p3,ShuxinLin/peloton,apavlo/peloton,prashasthip/peloton,wangziqi2016/peloton,ShuxinLin/peloton,cmu-db/peloton,malin1993ml/peloton,apavlo/peloton,AllisonWang/peloton,PauloAmora/peloton,malin1993ml/peloton,cmu-db/peloton,PauloAmora/peloton,ShuxinLin/peloton,AngLi-Leon/peloton,eric-haibin-lin/peloton-1,eric-haibin-lin/peloton-1,wangziqi2016/peloton,yingjunwu/peloton,AllisonWang/peloton,AngLi-Leon/peloton,apavlo/peloton,PauloAmora/peloton,prashasthip/peloton,AngLi-Leon/peloton,yingjunwu/peloton,cmu-db/peloton,PauloAmora/peloton,phisiart/peloton-p3,malin1993ml/peloton,vittvolt/15721-peloton,haojin2/peloton,AllisonWang/peloton,wangziqi2016/peloton,ShuxinLin/peloton,eric-haibin-lin/peloton-1,AngLi-Leon/peloton,vittvolt/peloton,phisiart/peloton-p3,AngLi-Leon/peloton,ShuxinLin/peloton,malin1993ml/peloton,jessesleeping/iso_peloton,yingjunwu/peloton,vittvolt/15721-peloton,eric-haibin-lin/peloton-1,vittvolt/peloton,phisiart/peloton-p3,vittvolt/peloton,haojin2/peloton,jessesleeping/iso_peloton,seojungmin/peloton,vittvolt/15721-peloton,seojungmin/peloton,prashasthip/peloton,haojin2/peloton,AllisonWang/peloton,seojungmin/peloton,eric-haibin-lin/peloton-1,haojin2/peloton,AllisonWang/peloton,haojin2/peloton,AllisonWang/peloton,phisiart/peloton-p3,prashasthip/peloton,yingjunwu/peloton,malin1993ml/peloton,jessesleeping/iso_peloton,wangziqi2016/peloton,vittvolt/peloton,cmu-db/peloton,vittvolt/15721-peloton,cmu-db/peloton