Skip ACL recode loop for intermediate ARF layers
Skip ACL recode loop for intermediate ARF layers

Speed up the encoding time by ~20% for multi-layer ARF system.

Change-Id: I16de1cfed7cd1815cf0269eb4f90ad74fdf087ee

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