anchor.diff:        }
         target = target.parentNode;
       }
  -  }
  -  
  +    return -1;
  +  }
   }
  
positive.code: import 'dart:mirrors';
  
  import 'package:polymer/polymer.dart';
  import 'package:polymer_elements/polymer_selection/polymer_selection.dart' show PolymerSelection;
  
  @CustomTag('polymer-selector')
  class PolymerSelector extends PolymerElement {
  
negative.code:     //from blowing up. I'm not sure that's reasoable.
      if (this.selectedProperty != null && this.selectedProperty.isNotEmpty) {
        //Note: Reflection is required to work properly with checkboxes
        try {
            // polymer-ui-submenu-item works only with this
            reflect(item).setField(new Symbol('${this.selectedProperty}'), isSelected);
        } catch(e) { // required for polymer_ui_breadcrumbs (when an attribute is set on a DOM element
            if(isSelected) {
              item.attributes[this.selectedProperty] = isSelected.toString();
            } else {
              item.attributes.remove(this.selectedProperty);
            }
         }
      }
    }
    
  