public static int encodeBlobVar(PositionedByteRange dst, byte[] val, Order ord) {
    return encodeBlobVar(dst, val, 0, null != val ? val.length : 0, ord);
  }
Encode a blob value using a modified varint encoding scheme.
@return the number of bytes written.
@see #encodeBlobVar(PositionedByteRange, byte[], int, int, Order)
hbase-common/src/main/java/org/apache/hadoop/hbase/util/OrderedBytes.java