code: public void fill3_1(byte[] bits, ByteBufferWrapper ab) {
        int bitoff = ab.get2();
        int nbytes = ab.get2();
        fill_1(bits, ab.position(), nbytes<<3, bitoff);
        ab.skip(nbytes);  // Skip inline bitset
      }
docs: /* SET IN STONE FOR MOJO VERSION "1.10" AND OLDER - DO NOT CHANGE