anchor.diff:  
           // position the square
           final etx = se.addTransform();
  -        etx.setToTranslation(coords.Item1 * SquareElement._size, coords.Item2 * SquareElement._size);
  +        etx.setToTranslation(
  +            _edgeOffset + coords.Item1 * SquareElement._size,
  +            _edgeOffset + coords.Item2 * SquareElement._size);
   
           _elements[i] = se;
         }
  
positive.code: class GameElement extends ElementParentImpl {
    final bool _targetMode;
    final dartlib.EventHandle _targetChanged;
  
  
negative.code:       size = const dartlib.Size(100, 100);
      } else {
        size = new dartlib.Size(
            SquareElement._size * value.field.width + _edgeOffset * 2,
            SquareElement._size * value.field.height + _edgeOffset * 2);
      }
    }
  
  