Remove frog from the repository.

frog/tests/await/nested_function2_test.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.
-
-// The next line is used to tell test.dart that this test is run by invoking
-// awaitc.dart and passing this file as an argument (e.g. frog
-// frog/await/awaitc.dart test.dart):
-// VMOptions=frog/await/awaitc.dart
-
-// Await within a lambda function.
-
-#import("await_test_helper.dart");
-
-main() {
-  bool called = false;
-  func() {
-    final f = futureOf(3);
-    final x = await f;
-    Expect.equals(3, x);
-    called = true;
-  }
-  Expect.equals(false, called);
-  final f2 = func();
-  Expect.equals(false, called);
-  await f2;
-  Expect.equals(true, called);
-}