Cast buffer offset to int64_t
Cast buffer offset to int64_t

To prevent integer overflow with extreme frame sizes.

Change-Id: Ib77f1c11f0264257d9e6c162f474d637592e7b09

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