text wierdness

main.dart

// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'package:flutter/material.dart';
import 'package:flutter/widgets.dart';

void main() =>
  runApp(
    MaterialApp(home: Scaffold(body: ListView(
      children: [
        Text('Hello, world!',
          key: Key('title'),
        ),
         Text('Back',
          key: Key('title'),
        ),
        Text('Forward',
          key: Key('title'),
        ),
        Text('Hello, world!',
          key: Key('title'),
        ),
         Text('Back',
          key: Key('title'),
        ),
        Text('Forward',
          key: Key('title'),
        ),
          Text('Hello, world!',
          key: Key('title'),
        ),
         Text('Back',
          key: Key('title'),
        ),
        Text('Forward',
          key: Key('title'),
        ),
        Text('Hello, world!',
          key: Key('title'),
        ),
         Text('Back',
          key: Key('title'),
        ),
        Text('Forward',
          key: Key('title'),
        ),
        for (var i = 0; i < 100; i++)
          Container(height: 100, color: Colors.red)
      ]
    )
  )));