Split up some slow pub tests and mark some scheduled_test tests as slow.

utils/tests/pub/lish/package_validation_has_an_error_test.dart

+// Copyright (c) 2013, 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 'dart:json' as json;
+
+import 'package:scheduled_test/scheduled_test.dart';
+import 'package:scheduled_test/scheduled_server.dart';
+
+import '../descriptor.dart' as d;
+import '../test_pub.dart';
+import 'utils.dart';
+
+main() {
+  initConfig();
+  setUp(d.validPackage.create);
+
+  integration('package validation has an error', () {
+    var pkg = packageMap("test_pkg", "1.0.0");
+    pkg.remove("homepage");
+    d.dir(appPath, [d.pubspec(pkg)]).create();
+
+    var server = new ScheduledServer();
+    var pub = startPublish(server);
+
+    pub.shouldExit(0);
+    expect(pub.remainingStderr(), completion(contains(
+        "Sorry, your package is missing a requirement and can't be published "
+        "yet.")));
+  });
+}