Remove barback from the repo.

pkg/barback/test/static_provider_test.dart

-// Copyright (c) 2014, 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 barback.test.static_provider_test;
-
-import 'package:scheduled_test/scheduled_test.dart';
-
-import 'utils.dart';
-
-main() {
-  initConfig();
-  test("gets a static source asset", () {
-    initStaticGraph(["app|foo.txt"], staticPackages: ["app"]);
-    expectAsset("app|foo.txt");
-    buildShouldSucceed();
-  });
-
-  test("doesn't get a nonexistent static source asset", () {
-    initStaticGraph(["app|foo.txt"], staticPackages: ["app"]);
-    expectNoAsset("app|bar.txt");
-  });
-
-  test("a transformer can see a static asset", () {
-    initStaticGraph({
-      "static|b.inc": "b",
-      "app|a.txt": "static|b.inc"
-    }, staticPackages: ["static"], transformers: {
-      "app": [[new ManyToOneTransformer("txt")]]
-    });
-    updateSources(["app|a.txt"]);
-    expectAsset("app|a.out", "b");
-  });
-
-  test("can list all static assets", () {
-    initStaticGraph(["app|foo.txt", "app|bar.txt", "app|baz.txt"],
-        staticPackages: ["app"]);
-    expectAllAssets(["app|foo.txt", "app|bar.txt", "app|baz.txt"]);
-  });
-}