replace video clips used in vp9 datarate CBR tests.
replace video clips used in vp9 datarate CBR tests.

replace hantro_collage with niklas vga clip.

Change-Id: I79b89ce12823095a5ee75025b2ddce9e8ef1452a

webmproject/libvpx,ShiftMediaProject/libvpx,webmproject/libvpx,ShiftMediaProject/libvpx,ShiftMediaProject/libvpx,ShiftMediaProject/libvpx,webmproject/libvpx,webmproject/libvpx,ShiftMediaProject/libvpx,webmproject/libvpx,webmproject/libvpx