Add compiler error when instantiating abstract class

tests/language/empty_body_member_negative_test.dart

Index: tests/language/empty_body_member_negative_test.dart
===================================================================
--- tests/language/empty_body_member_negative_test.dart	(revision 11549)
+++ tests/language/empty_body_member_negative_test.dart	(working copy)
@@ -1,15 +0,0 @@
-// 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.
-
-class EmptyBodyMemberNegativeTest {
-  int foo();
-
-  static testMain() {
-  }
-}
-
-
-main() {
-  EmptyBodyMemberNegativeTest.testMain();
-}