anchor.diff:  import 'package:angular_components/material_datepicker/range.dart';
   import 'package:angular_components/material_popup/material_popup.dart';
   import 'package:angular_components/material_select/dropdown_button.dart';
  +import 'package:angular_components/mixins/focusable_mixin.dart';
   import 'package:angular_components/model/date/date.dart';
   import 'package:angular_components/model/date/date_formatter.dart';
   import 'package:angular_components/model/observable/observable.dart';
  
positive.code: import 'package:angular_components/material_datepicker/comparison.dart';
  import 'package:angular_components/material_datepicker/comparison_option.dart';
  import 'package:angular_components/material_datepicker/config.dart';
  import 'package:angular_components/material_datepicker/date_range_editor_host.dart';
  import 'package:angular_components/material_datepicker/date_range_editor.dart';
  import 'package:angular_components/material_datepicker/model.dart';
  import 'package:angular_components/material_datepicker/module.dart';
  import 'package:angular_components/material_datepicker/next_prev_buttons.dart';
  
negative.code:   Focusable _dateRangeEditor;
    bool _focusOnDateRangeEditorInit = false;
    PopupSizeProvider _popupSizeProvider;
  
    @ViewChild(ButtonDirective)
    set focusableElement(ButtonDirective button) {
      focusable = button;
    }
  
    @Deprecated('Use [presets] instead.')
    @Input('predefinedRanges')
  