* com.google.common.io.ByteStreams#newDataOutput()} to get a growable buffer.
   */
  public static byte[] toByteArray(long value) {
    // Note that this code needs to stay compatible with GWT, which has known
    // bugs when narrowing byte casts of long values occur.
    byte[] result = new byte[8];
    for (int i = 7; i >= 0; i--) {
      result[i] = (byte) (value & 0xffL);