anchor.diff:  
     final bool Function(T element) includeCallback;
   
  -  final String tooltip;
  +  final String? tooltip;
   
     final bool enabledByDefault;
   
  
positive.code: 
  class QueryFilterArgument {
    QueryFilterArgument({
      @required this.keys,
      this.values = const [],
      this.isNegative = false,
    });
  
negative.code: 
    Widget _buildQueryInstructions() {
      return Text(
        widget.queryInstructions!,
        style: Theme.of(context).subtleTextStyle,
      );
    }
  
    void _resetFilters() {
      queryTextFieldController.clear();
      for (final toggleFilter in widget.toggleFilters ?? []) {
        toggleFilter.enabled.value = toggleFilter.enabledByDefault;
      }
    }
  }
  
  class ToggleFilterElement extends StatelessWidget {
    const ToggleFilterElement({Key? key, required this.filter}) : super(key: key);
  
    final ToggleFilter filter;
  
  