anchor.diff:  // BSD-style license that can be found in the LICENSE file.
   
   import 'dart:async';
  +import 'dart:html';
   
   import 'package:angular/angular.dart';
  +import 'package:angular_components/utils/angular/css/css.dart';
   import 'package:angular_components/content/deferred_content.dart';
   import 'package:angular_components/content/deferred_content_aware.dart';
   import 'package:angular_components/laminate/enums/alignment.dart';
  
positive.code:   final TooltipController _tooltipController;
    final ChangeDetectorRef _changeDetector;
  
    MaterialPaperTooltipComponent(this._tooltipController, this._changeDetector);
  
    @ViewChild(MaterialPopupComponent)
    set popupChild(MaterialPopupComponent popup) {
  
negative.code:   visibility: Visibility.all,
  )
  class MaterialPaperTooltipComponent implements DeferredContentAware, Tooltip {
    // To allow for more flexible styling, classes specified on the host are
    // re-applied to material-popup.
    final String popupClassName;
  
    PopupSource _tooltipSource;
    PopupSource get popupSource => _tooltipSource;
  
  