Revert r25914 because of clang build error.

tests/language/large_integer_equality_vm_test.dart

Index: tests/language/large_integer_equality_vm_test.dart
===================================================================
--- tests/language/large_integer_equality_vm_test.dart	(revision 25914)
+++ tests/language/large_integer_equality_vm_test.dart	(working copy)
@@ -1,11 +0,0 @@
-// 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.
-
-import "package:expect/expect.dart";
-
-main() {
-  var x = 81985529216486895;
-  Expect.isTrue(x == x.toDouble());
-  Expect.isTrue(x.toDouble() == x);
-}