function readLength() {
    var byte = delta[deltaOffset++];
    var length = byte & 0x7f;
    var shift = 7;
    while (byte & 0x80) {
      byte = delta[deltaOffset++];
      length |= (byte & 0x7f) << shift;
      shift += 7;
    }
    return length;
  }
function readLength() {
    var byte = delta[deltaOffset++];
    var length = byte & 0x7f;
    var shift = 7;
    while (byte & 0x80) {
      byte = delta[deltaOffset++];
      length |= (byte & 0x7f) << shift;
      shift += 7;
    }
    return length;
  }
function readLength ( ) { var byte = delta [ deltaOffset ++ ] ; var length = byte & 0x7f ; var shift = 7 ; while ( byte & 0x80 ) { byte = delta [ deltaOffset ++ ] ; length |= ( byte & 0x7f ) << shift ; shift += 7 ; } return length ; }
Read a variable length number our of delta and move the offset.
Read a variable length number our of delta and move the offset .