anchor.diff:      testWidgets((WidgetTester tester) {
         tester.pumpWidget(new Markdown(data: "[Link Text](href)"));
   
  -      Element textElement = tester.findElement((Element element) => element.widget is RichText);
  -      RichText textWidget = textElement.widget;
  +      RichText textWidget = tester.widgets.firstWhere((Widget widget) => widget is RichText);
         TextSpan span = textWidget.text;
   
         expect(span.children[0].recognizer.runtimeType, equals(TapGestureRecognizer));
  
positive.code:     testWidgets((WidgetTester tester) {
        tester.pumpWidget(new MarkdownBody(data: "Hello"));
  
        List<Element> elements = _listElements(tester);
        _expectWidgetTypes(elements, <Type>[MarkdownBody, Column, Container, Padding, RichText]);
        _expectTextStrings(elements, <String>["Hello"]);
      });
    });
  
  
negative.code:     testWidgets((WidgetTester tester) {
        tester.pumpWidget(new MarkdownBody(data: "1. Item 1\n1. Item 2\n2. Item 3"));
  
        Iterable<Widget> widgets = tester.widgets;
        _expectTextStrings(widgets, <String>[
          "1.",
          "Item 1",
          "2.",
  