Remove frogsh.

dart/frog/tests/await/src/await_test_helper.dart

-// Copyright (c) 2011, 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.
-
-// A library used by await tests.
-#library("await_test_helper.dart");
-
-#import("../../../lib/node/node.dart");
-
-/** Returns a future that completes with [value] after calling [setTimeout]. */
-Future futureOf(value) {
-  final c = new Completer();
-  final f = c.future;
-  setTimeout(() { c.complete(value); }, 0);
-  return f;
-}
-
-Future errorOf(error) {
-  final c = new Completer();
-  final f = c.future;
-  setTimeout(() { c.completeException(error); }, 0);
-  return f;
-}