updateByte method
Add one byte of data to the digested input.
Implementation
@override
void updateByte(int inp) {
  _wordBuffer[_wordBufferOffset++] = inp;
  if (_wordBufferOffset == _wordBuffer.length) {
    _processWord(_wordBuffer, 0);
    _wordBufferOffset = 0;
  }
  _byteCount1.sum(1);
}