anchor.diff:  
     updatePreviewSize(div);
   
  +  registerEvents(div);
  +}
  +
  +void registerEvents(DivElement div) {
     var spans = div.querySelectorAll("form span");
     for (HtmlElement span in spans) {
       span.onClick.listen(onDimensionLabelClick);
  
positive.code:   parent.querySelectorAll("span").style.display = 'none';
    parent.querySelectorAll("input").style.display = 'inline';
    (parent.querySelector("input." + target.className) as InputElement).select();
  
  
  }
  
  void onDimensionInputBlur(MouseEvent e) {
  
negative.code: HtmlElement container;
  HtmlElement draggedElement;
  num previewCounter = 0;
  SortableGroup sortableGroup = new SortableGroup();
  
  void main() {
    container = querySelector('#container');
  