code: final void normalize() {
          if (intLen == 0) {
              offset = 0;
              return;
          }
  
          int index = offset;
          if (value[index] != 0)
              return;
  
          int indexBound = index+intLen;
          do {
              index++;
          } while(index < indexBound && value[index] == 0);
  
          int numZeros = index - offset;
          intLen -= numZeros;
          offset = (intLen == 0 ?  0 : offset+numZeros);
      }
docs: Ensure that the MutableBigInteger is in normal form, specifically
  making sure that there are no leading zeros, and that if the
  magnitude is zero, then intLen is zero.