Add flutter_web samples (#75)

web/gallery/lib/demo/material/text_demo.dart

@@ -0,0 +1,52 @@
+// Copyright 2018 The Chromium 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_web/material.dart';
+
+class TextDemo extends StatelessWidget {
+  static const routeName = '/material/text';
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(
+        title: Text('Text'),
+        centerTitle: true,
+      ),
+      body: ListView(
+        children: [
+          pad(Text('Single line of text')),
+          Divider(),
+          // Single line with many whitespaces in between.
+          pad(Text('     Text with       a   lot of    whitespace     ')),
+          Divider(),
+          // Forced multi-line because of the \n.
+          pad(Text('Text with a newline\ncharacter should render in 2 lines')),
+          Divider(),
+          // Multi-line with regular whitespace.
+          pad(Text(
+            '''Lorem ipsum dolor sit amet, consectetur adipiscing elit. Maecenas auctor
+vel ligula eget fermentum. Integer mattis nulla vitae ullamcorper
+dignissim. Donec vel velit vel eros lobortis laoreet at sit amet turpis.
+Ut in orci blandit, rhoncus metus quis, finibus augue. Nullam a elit
+venenatis metus accumsan dapibus. Vestibulum imperdiet tristique viverra.''',
+          )),
+          Divider(),
+          // Multi-line with a lot of whitespace in between.
+          pad(Text(
+            '''
+             Lorem ipsum dolor sit amet,            consectetur adipiscing elit.
+             Maecenas auctor vel ligula eget                          fermentum.
+             Integer mattis nulla                   vitae ullamcorper dignissim.
+             Donec vel velit vel eros lobortis laoreet at sit amet turpis.''',
+          )),
+          Divider(),
+        ],
+      ),
+    );
+  }
+
+  Padding pad(Widget child) =>
+      Padding(padding: EdgeInsets.all(12), child: child);
+}