Start pulling pub from its own repo.

sdk/lib/_internal/pub/test/dart2js/source_maps_include_core_libs_in_subdirectory_test.dart

-// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS d.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:path/path.dart' as path;
-import 'package:scheduled_test/scheduled_test.dart';
-
-import '../descriptor.dart' as d;
-import '../serve/utils.dart';
-import '../test_pub.dart';
-
-main() {
-  initConfig();
-
-  // This test is a bit shaky. Since dart2js is free to inline things, it's
-  // not precise as to which source libraries will actually be referenced in
-  // the source map. But this tries to use a type in the core library
-  // (Duration) and validate that its source ends up in the source map.
-  integration("Dart core libraries are available to source maps when the "
-      "build directory is a subdirectory", () {
-    d.dir(appPath, [
-      d.appPubspec(),
-      d.dir("web", [
-        d.dir("sub", [
-          d.file("main.dart", "main() => new Duration().toString();")
-        ])
-      ])
-    ]).create();
-
-    var webSub = path.join("web", "sub");
-    pubServe(args: [webSub]);
-
-    requestShouldSucceed("main.dart.js.map",
-        contains(r"packages/$sdk/lib/core/duration.dart"),
-        root: webSub);
-    requestShouldSucceed(r"packages/$sdk/lib/core/duration.dart",
-        contains("class Duration"),
-        root: webSub);
-
-    endPubServe();
-  });
-}