code: function() {
      this.$$animate.setClass(this.$$element, PRISTINE_CLASS, DIRTY_CLASS + ' ' + SUBMITTED_CLASS);
      this.$dirty = false;
      this.$pristine = true;
      this.$submitted = false;
      forEach(this.$$controls, function(control) {
        control.$setPristine();
      });
    }
docs: @ngdoc method
  @name form.FormController#$setPristine
  
  @description
  Sets the form to its pristine state.
  
  This method sets the form's `$pristine` state to true, the `$dirty` state to false, removes
  the `ng-dirty` class and adds the `ng-pristine` class. Additionally, it sets the `$submitted`
  state to false.
  
  This method will also propagate to all the controls contained in this form.
  
  Setting a form back to a pristine state is often useful when we want to 'reuse' a form after
  saving or resetting it.