anchor.diff:  
   import 'dart:async';
   import 'dart:html';
  -import 'dart:js';
   
   import 'package:meta/meta.dart';
   
  
positive.code: 
          currentColumnIndex++;
  
          // TODO(dantup): Should we make CoreElement expose ClassList instead
          // of having flat strings?
          tableCell.element.classes.clear();
          if (column.cssClass != null) {
            column.cssClass.split(' ').forEach(tableCell.clazz);
  
negative.code: 
    void _init() {
      element.add(_table);
  
      // handle hey events
      _table.onKeyDown.listen((KeyboardEvent e) {
        int indexOffset;
        // TODO(dantup): PgUp/PgDown/Home/End?
        if (e.keyCode == KeyCode.UP) {
          indexOffset = -1;
        } else if (e.keyCode == KeyCode.DOWN) {
          indexOffset = 1;
        }
  
        if (indexOffset == null) {
          return;
        }
  
  