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

tests/corelib/uri_normalize_path_test.dart

-// 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.
-
-library uriNormalizePathTest;
-
-import "package:expect/expect.dart";
-
-test(String path, String normalizedPath) {
-  for (var scheme in ["http", "file", "unknown"]) {
-    for (var auth in [[null, "hostname", null],
-                      ["userinfo", "hostname", 1234],
-                      [null, null, null]]) {
-      for (var query in [null, "query"]) {
-        for (var fragment in [null, "fragment"]) {
-          var base = new Uri(scheme: scheme,
-                             userInfo: auth[0],
-                             host: auth[1],
-                             port: auth[2],
-                             path: path,
-                             query: query,
-                             fragment: fragment);
-          var expected = base.replace(path:
-              (base.hasAuthority && normalizedPath.isEmpty) ? "/"
-                                                            : normalizedPath);
-          var actual = base.normalizePath();
-          Expect.equals(expected, actual, "$base");
-        }
-      }
-    }
-  }
-}
-testNoChange(String path) {
-  test(path, path);
-}
-
-main() {
-  testNoChange("foo/bar/baz");
-  testNoChange("/foo/bar/baz");
-  testNoChange("foo/bar/baz/");
-  test("foo/bar/..", "foo/");
-  test("foo/bar/.", "foo/bar/");
-  test("foo/./bar/../baz", "foo/baz");
-  test("../../foo", "foo");
-  test("./../foo", "foo");
-  test("./../", "");
-  test("./../.", "");
-  test("foo/bar/baz/../../../../qux", "/qux");
-  test("/foo/bar/baz/../../../../qux", "/qux");
-  test(".", "");
-  test("..", "");
-  test("/.", "/");
-  test("/..", "/");
-}