Delete a bunch of packages that are now on GitHub.

pkg/scheduled_test/lib/src/future_group.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.
-
-library future_group;
-
-import 'dart:async';
-
-/// A completer that waits until all added [Future]s complete.
-// TODO(rnystrom): Copied from web_components. Remove from here when it gets
-// added to dart:core. (See #6626.)
-class FutureGroup<T> {
-  int _pending = 0;
-  Completer<List<T>> _completer = new Completer<List<T>>();
-  final List<Future<T>> futures = <Future<T>>[];
-  bool completed = false;
-
-  final List<T> _values = <T>[];
-
-  /// Wait for [task] to complete.
-  Future<T> add(Future<T> task) {
-    if (completed) {
-      throw new StateError("The FutureGroup has already completed.");
-    }
-
-    _pending++;
-    futures.add(task.then((value) {
-      if (completed) return;
-
-      _pending--;
-      _values.add(value);
-
-      if (_pending <= 0) {
-        completed = true;
-        _completer.complete(_values);
-      }
-    }).catchError((error, stackTrace) {
-      if (completed) return;
-
-      completed = true;
-      _completer.completeError(error, stackTrace);
-    }));
-
-    return task;
-  }
-
-  Future<List> get future => _completer.future;
-}
-