Add data-URI support class to dart:core (next to Uri).

tests/corelib/uri_base_test.dart

Index: tests/corelib/uri_base_test.dart
diff --git a/tests/corelib/uri_base_test.dart b/tests/corelib/uri_base_test.dart
deleted file mode 100644
index 0954aabeeed9b373a164d69b7673d8e529a7600d..0000000000000000000000000000000000000000
--- a/tests/corelib/uri_base_test.dart
+++ /dev/null
@@ -1,15 +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"));
-  }
-}