Migrate test block 30 + corelib portion of block 31 to Dart 2.0.

tests/corelib_strong/uri_base_test.dart

Index: tests/corelib_strong/uri_base_test.dart
diff --git a/tests/corelib_strong/uri_base_test.dart b/tests/corelib_strong/uri_base_test.dart
deleted file mode 100644
index a54a28774a59eb5fd44df9cf74a9361ed4863e8a..0000000000000000000000000000000000000000
--- a/tests/corelib_strong/uri_base_test.dart
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright (c) 2012, 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";
-
-main() {
-  try {
-    Uri base = Uri.base;
-    Expect.isTrue(Uri.base.scheme == "file" || Uri.base.scheme == "http");
-  } on UnsupportedError catch (e) {
-    Expect.isTrue(e.toString().contains("'Uri.base' is not supported"));
-  }
-}