Add ref frame rate cost to non-RD mode decision
Add ref frame rate cost to non-RD mode decision

This commit adds a heuristic rate cost of reference frame to the
non-RD mode decision. It improves the compression performance of
speed -6 by 0.31% and speed -5 by 0.69%.

Change-Id: If7f3b45519d49b2cb640bcb7316a254efc8be446

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