Replace string uses with code units in Json parser.

samples/buildbot/tests/json_test.dart

+// Copyright (c) 2015, the Fletch project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE.md file.
+
+import 'dart:io';
+
+import 'package:expect/expect.dart';
+
+import '../json.dart';
+
+void main() {
+  testParser();
+}
+
+void testParser() {
+  Expect.equals(null, new JsonParser('null').parse());
+  Expect.equals(true, new JsonParser('true').parse());
+  Expect.equals(false, new JsonParser('false').parse());
+  Expect.equals(42, new JsonParser('42').parse());
+  Expect.equals("hello world", new JsonParser('"hello world"').parse());
+
+  Expect.listEquals(
+    [true, "hello world", 42],
+    new JsonParser('[true,"hello world",42]').parse());
+
+  Expect.listEquals(
+    [true, "hello world", 42],
+    new JsonParser(' [ true , "hello world" , 42 ] ').parse());
+
+  Expect.mapEquals(
+    {"foo":true, "bar":"hello world", "baz":42},
+    new JsonParser('{"foo":true,"bar":"hello world","baz":42}').parse());
+
+  Expect.mapEquals(
+     {"foo":true, "bar":"hello world", "baz":42},
+     new JsonParser(' { "foo" :\t true , "bar" : "hello world" , "baz" : 42 } ')
+   .parse());

[Anders Johnsen, 2015/03/05 07:35:31]

Expect.throws(() => new JsonParser('[1 2 3 4 5]').parse());

[zerny-google, 2015/03/05 08:12:31]

Done.

+}