Revert two Kernel changes that were causing test failures.

tests/language_2/assign_top_method_test.dart

Index: tests/language_2/assign_top_method_test.dart
diff --git a/tests/language_2/assign_top_method_test.dart b/tests/language_2/assign_top_method_test.dart
deleted file mode 100644
index 1b889b915f42bc0067536a19f35a08847019c31c..0000000000000000000000000000000000000000
--- a/tests/language_2/assign_top_method_test.dart
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright (c) 2012, 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 "package:expect/expect.dart";
-
-method() {
-  return 0;
-}
-
-main() {
-  // Illegal, can't change a top level method
-  /*@compile-error=unspecified*/ method = () { return 1; };
-}