anchor.diff:                      top: 0.0,
                       child: new Tooltip(
                         key: key,
  -                      message: 'TIP',
  +                      message: tooltipText,
                         height: 20.0,
                         padding: const EdgeInsets.all(5.0),
                         verticalOffset: 20.0,
  
positive.code:     await tester.pump(kLongPressTimeout);
      await tester.pump(const Duration(milliseconds: 10));
      await gesture.up();
      expect(find.text('TIP'), findsOneWidget);
      await tester.tap(tooltip);
      await tester.pump(const Duration(milliseconds: 10));
      gesture = await tester.startGesture(tester.getCenter(tooltip));
      await tester.pump();
      await tester.pump(const Duration(milliseconds: 300));
      expect(find.text('TIP'), findsNothing);
      await tester.pump(kLongPressTimeout);
      expect(find.text('TIP'), findsOneWidget);
      await tester.pump(kLongPressTimeout);
      expect(find.text('TIP'), findsOneWidget);
      gesture.up();
    });
  
  
negative.code:                     top: 299.0,
                      child: new Tooltip(
                        key: key,
                        message: tooltipText,
                        height: 190.0,
                        padding: const EdgeInsets.all(0.0),
                        verticalOffset: 100.0,
  