merged optimiz_b_16x16() into optmize_b()
merged optimiz_b_16x16() into optmize_b()

The commit changed the trellis quantization function optimize_b() to
work for MBs using all transform sizes, and eliminated the function
for MB using 16x16 transform only, optimize_b_16x16.

Change-Id: I3fa650587ab5198ed16315b38754783a72b33ba2

running770/libvpx,ittiamvpx/libvpx-1,gshORTON/webm.libvpx,webmproject/libvpx,cinema6/libvpx,Maria1099/webm.libvpx,abwiz0086/webm.libvpx,ShiftMediaProject/libvpx,goodleixiao/vpx,jacklicn/webm.libvpx,shacklettbp/aom,kleopatra999/webm.libvpx,openpeer/libvpx_new,Suvarna1488/webm.libvpx,felipebetancur/libvpx,luctrudeau/aom,thdav/aom,openpeer/libvpx_new,luctrudeau/aom,jdm/libvpx,GrokImageCompression/aom,WebRTC-Labs/libvpx,charup/https---github.com-webmproject-libvpx-,kim42083/webm.libvpx,ShiftMediaProject/libvpx,ittiamvpx/libvpx,altogother/webm.libvpx,zofuthan/libvpx,thdav/aom,iniwf/webm.libvpx,matanbs/vp982,jacklicn/webm.libvpx,lyx2014/libvpx_c,altogother/webm.libvpx,jmvalin/aom,stewnorriss/libvpx,turbulenz/libvpx,VTCSecureLLC/libvpx,iniwf/webm.libvpx,Laknot/libvpx,Topopiccione/libvpx,smarter/aom,jdm/libvpx,turbulenz/libvpx,altogother/webm.libvpx,Topopiccione/libvpx,reimaginemedia/webm.libvpx,hsueceumd/test_hui,mwgoldsmith/libvpx,thdav/aom,shyamalschandra/libvpx,reimaginemedia/webm.libvpx,sanyaade-teachings/libvpx,turbulenz/libvpx,gshORTON/webm.libvpx,stewnorriss/libvpx,Topopiccione/libvpx,gshORTON/webm.libvpx,jdm/libvpx,webmproject/libvpx,shacklettbp/aom,vasilvv/esvp8,webmproject/libvpx,vasilvv/esvp8,luctrudeau/aom,Laknot/libvpx,Acidburn0zzz/webm.libvpx,iniwf/webm.libvpx,jacklicn/webm.libvpx,mbebenita/aom,Laknot/libvpx,pcwalton/libvpx,matanbs/vp982,Distrotech/libvpx,ittiamvpx/libvpx-1,GrokImageCompression/aom,webmproject/libvpx,gshORTON/webm.libvpx,ShiftMediaProject/libvpx,pcwalton/libvpx,felipebetancur/libvpx,mwgoldsmith/libvpx,sanyaade-teachings/libvpx,WebRTC-Labs/libvpx,mwgoldsmith/vpx,running770/libvpx,n4t/libvpx,Maria1099/webm.libvpx,altogother/webm.libvpx,abwiz0086/webm.libvpx,ittiamvpx/libvpx,kalli123/webm.libvpx,Maria1099/webm.libvpx,pcwalton/libvpx,thdav/aom,jacklicn/webm.libvpx,zofuthan/libvpx,webmproject/libvpx,jacklicn/webm.libvpx,charup/https---github.com-webmproject-libvpx-,vasilvv/esvp8,mbebenita/aom,matanbs/vp982,turbulenz/libvpx,ittiamvpx/libvpx-1,mwgoldsmith/vpx,Acidburn0zzz/webm.libvpx,matanbs/webm.libvpx,Laknot/libvpx,Acidburn0zzz/webm.libvpx,n4t/libvpx,abwiz0086/webm.libvpx,cinema6/libvpx,matanbs/vp982,jdm/libvpx,liqianggao/libvpx,matanbs/vp982,gshORTON/webm.libvpx,ShiftMediaProject/libvpx,mwgoldsmith/libvpx,matanbs/webm.libvpx,zofuthan/libvpx,kalli123/webm.libvpx,mbebenita/aom,shacklettbp/aom,vasilvv/esvp8,stewnorriss/libvpx,liqianggao/libvpx,Acidburn0zzz/webm.libvpx,Maria1099/webm.libvpx,ittiamvpx/libvpx,running770/libvpx,ittiamvpx/libvpx,openpeer/libvpx_new,zofuthan/libvpx,liqianggao/libvpx,turbulenz/libvpx,lyx2014/libvpx_c,matanbs/vp982,Topopiccione/libvpx,VTCSecureLLC/libvpx,reimaginemedia/webm.libvpx,pcwalton/libvpx,kim42083/webm.libvpx,pcwalton/libvpx,openpeer/libvpx_new,Distrotech/libvpx,smarter/aom,mwgoldsmith/vpx,cinema6/libvpx,mwgoldsmith/vpx,lyx2014/libvpx_c,openpeer/libvpx_new,shyamalschandra/libvpx,turbulenz/libvpx,smarter/aom,Suvarna1488/webm.libvpx,hsueceumd/test_hui,ShiftMediaProject/libvpx,smarter/aom,hsueceumd/test_hui,iniwf/webm.libvpx,mwgoldsmith/vpx,kim42083/webm.libvpx,stewnorriss/libvpx,jdm/libvpx,Topopiccione/libvpx,turbulenz/libvpx,shareefalis/libvpx,running770/libvpx,reimaginemedia/webm.libvpx,shareefalis/libvpx,zofuthan/libvpx,matanbs/webm.libvpx,shareefalis/libvpx,kleopatra999/webm.libvpx,VTCSecureLLC/libvpx,Suvarna1488/webm.libvpx,mbebenita/aom,GrokImageCompression/aom,goodleixiao/vpx,abwiz0086/webm.libvpx,jacklicn/webm.libvpx,kim42083/webm.libvpx,abwiz0086/webm.libvpx,gshORTON/webm.libvpx,Distrotech/libvpx,reimaginemedia/webm.libvpx,goodleixiao/vpx,kalli123/webm.libvpx,sanyaade-teachings/libvpx,matanbs/vp982,mbebenita/aom,Laknot/libvpx,shacklettbp/aom,hsueceumd/test_hui,jdm/libvpx,luctrudeau/aom,mbebenita/aom,thdav/aom,vasilvv/esvp8,felipebetancur/libvpx,mwgoldsmith/libvpx,sanyaade-teachings/libvpx,shyamalschandra/libvpx,mwgoldsmith/libvpx,VTCSecureLLC/libvpx,shyamalschandra/libvpx,jmvalin/aom,pcwalton/libvpx,charup/https---github.com-webmproject-libvpx-,openpeer/libvpx_new,kim42083/webm.libvpx,Acidburn0zzz/webm.libvpx,abwiz0086/webm.libvpx,luctrudeau/aom,shacklettbp/aom,lyx2014/libvpx_c,luctrudeau/aom,smarter/aom,lyx2014/libvpx_c,altogother/webm.libvpx,reimaginemedia/webm.libvpx,goodleixiao/vpx,mbebenita/aom,charup/https---github.com-webmproject-libvpx-,kalli123/webm.libvpx,n4t/libvpx,running770/libvpx,charup/https---github.com-webmproject-libvpx-,kim42083/webm.libvpx,GrokImageCompression/aom,shareefalis/libvpx,jmvalin/aom,Topopiccione/libvpx,Maria1099/webm.libvpx,charup/https---github.com-webmproject-libvpx-,ittiamvpx/libvpx-1,hsueceumd/test_hui,shacklettbp/aom,ittiamvpx/libvpx-1,shareefalis/libvpx,hsueceumd/test_hui,iniwf/webm.libvpx,liqianggao/libvpx,matanbs/webm.libvpx,felipebetancur/libvpx,mwgoldsmith/vpx,webmproject/libvpx,VTCSecureLLC/libvpx,liqianggao/libvpx,Laknot/libvpx,Acidburn0zzz/webm.libvpx,Suvarna1488/webm.libvpx,vasilvv/esvp8,GrokImageCompression/aom,Suvarna1488/webm.libvpx,kleopatra999/webm.libvpx,thdav/aom,jmvalin/aom,sanyaade-teachings/libvpx,liqianggao/libvpx,cinema6/libvpx,Distrotech/libvpx,kalli123/webm.libvpx,WebRTC-Labs/libvpx,smarter/aom,felipebetancur/libvpx,vasilvv/esvp8,mbebenita/aom,ittiamvpx/libvpx,iniwf/webm.libvpx,Maria1099/webm.libvpx,WebRTC-Labs/libvpx,goodleixiao/vpx,lyx2014/libvpx_c,felipebetancur/libvpx,kalli123/webm.libvpx,jmvalin/aom,jmvalin/aom,kleopatra999/webm.libvpx,ittiamvpx/libvpx-1,altogother/webm.libvpx,stewnorriss/libvpx,kleopatra999/webm.libvpx,kleopatra999/webm.libvpx,GrokImageCompression/aom,VTCSecureLLC/libvpx,ittiamvpx/libvpx,WebRTC-Labs/libvpx,matanbs/webm.libvpx,cinema6/libvpx,Distrotech/libvpx,n4t/libvpx,turbulenz/libvpx,shyamalschandra/libvpx,zofuthan/libvpx,shyamalschandra/libvpx,Suvarna1488/webm.libvpx,Distrotech/libvpx,mbebenita/aom,stewnorriss/libvpx,cinema6/libvpx,n4t/libvpx,turbulenz/libvpx,running770/libvpx,mwgoldsmith/libvpx,cinema6/libvpx,matanbs/webm.libvpx,shareefalis/libvpx,goodleixiao/vpx