[Gallery] Fix directory structure (#312)

gallery/lib/demos/cupertino/cupertino_text_field_demo.dart

@@ -0,0 +1,66 @@
+// Copyright 2019 The Flutter team. 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/cupertino.dart';
+import 'package:gallery/l10n/gallery_localizations.dart';
+
+// BEGIN cupertinoTextFieldDemo
+
+class CupertinoTextFieldDemo extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    final localizations = GalleryLocalizations.of(context);
+    return CupertinoPageScaffold(
+      navigationBar: CupertinoNavigationBar(
+        automaticallyImplyLeading: false,
+        middle: Text(localizations.demoCupertinoTextFieldTitle),
+      ),
+      child: SafeArea(
+        child: ListView(
+          padding: const EdgeInsets.all(16),
+          children: [
+            Padding(
+              padding: const EdgeInsets.symmetric(vertical: 8),
+              child: CupertinoTextField(
+                placeholder: localizations.demoTextFieldEmail,
+                keyboardType: TextInputType.emailAddress,
+                clearButtonMode: OverlayVisibilityMode.editing,
+                autocorrect: false,
+              ),
+            ),
+            Padding(
+              padding: const EdgeInsets.symmetric(vertical: 8),
+              child: CupertinoTextField(
+                placeholder: localizations.rallyLoginPassword,
+                clearButtonMode: OverlayVisibilityMode.editing,
+                obscureText: true,
+                autocorrect: false,
+              ),
+            ),
+            CupertinoTextField(
+              prefix: Icon(
+                CupertinoIcons.padlock_solid,
+                size: 28,
+              ),
+              padding: EdgeInsets.symmetric(horizontal: 6, vertical: 12),
+              clearButtonMode: OverlayVisibilityMode.editing,
+              keyboardType: TextInputType.number,
+              decoration: BoxDecoration(
+                border: Border(
+                  bottom: BorderSide(
+                    width: 0,
+                    color: CupertinoColors.inactiveGray,
+                  ),
+                ),
+              ),
+              placeholder: localizations.demoCupertinoTextFieldPIN,
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}
+
+// END