Prevent integer overflow in choose_partitioning
Prevent integer overflow in choose_partitioning

Re-arrange the multiplication and right shift operations to avoid
integer overflow in choose_partitioning.

Change-Id: Ib4005cafb410a67c1960486471d75b6ebe38c4e0

jmvalin/aom,shareefalis/libvpx,matanbs/webm.libvpx,Maria1099/webm.libvpx,smarter/aom,smarter/aom,abwiz0086/webm.libvpx,lyx2014/libvpx_c,Suvarna1488/webm.libvpx,abwiz0086/webm.libvpx,lyx2014/libvpx_c,mwgoldsmith/vpx,webmproject/libvpx,webmproject/libvpx,running770/libvpx,kalli123/webm.libvpx,liqianggao/libvpx,lyx2014/libvpx_c,liqianggao/libvpx,kim42083/webm.libvpx,lyx2014/libvpx_c,mbebenita/aom,iniwf/webm.libvpx,jacklicn/webm.libvpx,VTCSecureLLC/libvpx,openpeer/libvpx_new,VTCSecureLLC/libvpx,kleopatra999/webm.libvpx,ittiamvpx/libvpx-1,stewnorriss/libvpx,gshORTON/webm.libvpx,mwgoldsmith/vpx,kalli123/webm.libvpx,zofuthan/libvpx,webmproject/libvpx,stewnorriss/libvpx,smarter/aom,kim42083/webm.libvpx,smarter/aom,Maria1099/webm.libvpx,mbebenita/aom,ShiftMediaProject/libvpx,Maria1099/webm.libvpx,altogother/webm.libvpx,VTCSecureLLC/libvpx,stewnorriss/libvpx,running770/libvpx,jmvalin/aom,reimaginemedia/webm.libvpx,altogother/webm.libvpx,goodleixiao/vpx,smarter/aom,thdav/aom,zofuthan/libvpx,shyamalschandra/libvpx,thdav/aom,shacklettbp/aom,mwgoldsmith/libvpx,lyx2014/libvpx_c,felipebetancur/libvpx,iniwf/webm.libvpx,reimaginemedia/webm.libvpx,mwgoldsmith/vpx,VTCSecureLLC/libvpx,shyamalschandra/libvpx,mwgoldsmith/libvpx,goodleixiao/vpx,kim42083/webm.libvpx,running770/libvpx,zofuthan/libvpx,running770/libvpx,GrokImageCompression/aom,goodleixiao/vpx,jacklicn/webm.libvpx,altogother/webm.libvpx,luctrudeau/aom,abwiz0086/webm.libvpx,jmvalin/aom,kleopatra999/webm.libvpx,shyamalschandra/libvpx,gshORTON/webm.libvpx,reimaginemedia/webm.libvpx,openpeer/libvpx_new,kleopatra999/webm.libvpx,Maria1099/webm.libvpx,Suvarna1488/webm.libvpx,mwgoldsmith/libvpx,lyx2014/libvpx_c,luctrudeau/aom,luctrudeau/aom,VTCSecureLLC/libvpx,kalli123/webm.libvpx,Suvarna1488/webm.libvpx,Distrotech/libvpx,shyamalschandra/libvpx,abwiz0086/webm.libvpx,ShiftMediaProject/libvpx,GrokImageCompression/aom,mwgoldsmith/vpx,jmvalin/aom,ittiamvpx/libvpx-1,shyamalschandra/libvpx,shareefalis/libvpx,matanbs/webm.libvpx,matanbs/webm.libvpx,mwgoldsmith/libvpx,ittiamvpx/libvpx-1,mbebenita/aom,reimaginemedia/webm.libvpx,Acidburn0zzz/webm.libvpx,GrokImageCompression/aom,iniwf/webm.libvpx,kalli123/webm.libvpx,Acidburn0zzz/webm.libvpx,mbebenita/aom,smarter/aom,stewnorriss/libvpx,shareefalis/libvpx,altogother/webm.libvpx,iniwf/webm.libvpx,shareefalis/libvpx,ittiamvpx/libvpx-1,Distrotech/libvpx,GrokImageCompression/aom,jacklicn/webm.libvpx,Acidburn0zzz/webm.libvpx,jmvalin/aom,mwgoldsmith/vpx,Topopiccione/libvpx,goodleixiao/vpx,mwgoldsmith/libvpx,liqianggao/libvpx,kleopatra999/webm.libvpx,matanbs/webm.libvpx,Suvarna1488/webm.libvpx,thdav/aom,Distrotech/libvpx,altogother/webm.libvpx,mbebenita/aom,jacklicn/webm.libvpx,Topopiccione/libvpx,Topopiccione/libvpx,liqianggao/libvpx,gshORTON/webm.libvpx,kalli123/webm.libvpx,openpeer/libvpx_new,shacklettbp/aom,goodleixiao/vpx,Topopiccione/libvpx,ShiftMediaProject/libvpx,mwgoldsmith/libvpx,GrokImageCompression/aom,ittiamvpx/libvpx-1,luctrudeau/aom,webmproject/libvpx,jacklicn/webm.libvpx,thdav/aom,matanbs/webm.libvpx,ShiftMediaProject/libvpx,shacklettbp/aom,liqianggao/libvpx,ShiftMediaProject/libvpx,running770/libvpx,iniwf/webm.libvpx,kim42083/webm.libvpx,altogother/webm.libvpx,reimaginemedia/webm.libvpx,felipebetancur/libvpx,webmproject/libvpx,shyamalschandra/libvpx,kleopatra999/webm.libvpx,Acidburn0zzz/webm.libvpx,stewnorriss/libvpx,felipebetancur/libvpx,kim42083/webm.libvpx,openpeer/libvpx_new,Acidburn0zzz/webm.libvpx,kleopatra999/webm.libvpx,running770/libvpx,thdav/aom,Maria1099/webm.libvpx,Acidburn0zzz/webm.libvpx,Topopiccione/libvpx,mbebenita/aom,felipebetancur/libvpx,luctrudeau/aom,mwgoldsmith/vpx,zofuthan/libvpx,liqianggao/libvpx,stewnorriss/libvpx,Suvarna1488/webm.libvpx,mbebenita/aom,webmproject/libvpx,shareefalis/libvpx,mbebenita/aom,Maria1099/webm.libvpx,openpeer/libvpx_new,mbebenita/aom,openpeer/libvpx_new,gshORTON/webm.libvpx,ittiamvpx/libvpx-1,matanbs/webm.libvpx,GrokImageCompression/aom,shacklettbp/aom,Distrotech/libvpx,shacklettbp/aom,shacklettbp/aom,gshORTON/webm.libvpx,felipebetancur/libvpx,luctrudeau/aom,kim42083/webm.libvpx,felipebetancur/libvpx,reimaginemedia/webm.libvpx,gshORTON/webm.libvpx,Distrotech/libvpx,abwiz0086/webm.libvpx,kalli123/webm.libvpx,zofuthan/libvpx,Distrotech/libvpx,zofuthan/libvpx,jmvalin/aom,Suvarna1488/webm.libvpx,goodleixiao/vpx,jacklicn/webm.libvpx,shareefalis/libvpx,Topopiccione/libvpx,thdav/aom,iniwf/webm.libvpx,abwiz0086/webm.libvpx,VTCSecureLLC/libvpx