anchor.diff:  
     get valid => _valid;
     set valid(value) {
  -    _invalid = false;
       _valid = true;
  -
       _animate.addClass(element, NG_VALID_CLASS);
       _animate.removeClass(element, NG_INVALID_CLASS);
     }
   
  -  get invalid => _invalid;
  +  get invalid => !_valid;
     set invalid(value) {
       _valid = false;
  -    _invalid = true;
  -
       _animate.addClass(element, NG_INVALID_CLASS);
       _animate.removeClass(element, NG_VALID_CLASS);
     }
  
positive.code:   get touched => _touched;
    set touched(value) {
      _touched = true;
      _untouched = false;
  
      _animate.addClass(element, NG_TOUCHED_CLASS);
      _animate.removeClass(element, NG_UNTOUCHED_CLASS);
      //as soon as one of the controls/models is touched
  
negative.code: 
    String _name;
    bool _dirty;
    bool _touched;
    bool _valid;
    bool _submit_valid;
  
    final Scope _scope;
  