Migrated test block 29 to Dart 2.0

tests/corelib_2/string_static_test.dart

+// Copyright (c) 2017, the Dart 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 file.
+
+import "package:expect/expect.dart";
+
+void main() {
+  testIllegalArgument();
+}
+
+void testIllegalArgument() {
+  String a = "Hello";
+  var c = a[2.2]; /*@compile-error=unspecified*/

[Bob Nystrom, 2017/07/21 22:03:26]

I would move the comment to here:

var c = a[/*@compile-error=unspecified*/2.2];

Eventually, we'd like to use these in the test runner to precisely validate
where the error is reported, and I think that's where it would show up.

+}