Remove deprecated Expect from the libraries.

tests/corelib/int_round_to_double_test.dart

Index: tests/corelib/int_round_to_double_test.dart
diff --git a/tests/corelib/int_round_to_double_test.dart b/tests/corelib/int_round_to_double_test.dart
index 39122a44accd3754de7b0c98d875ddc7aeec22f4..cc2a4caa28569f3a49ba2bd603b257530185cc6b 100644
--- a/tests/corelib/int_round_to_double_test.dart
+++ b/tests/corelib/int_round_to_double_test.dart
@@ -2,6 +2,8 @@
 // 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() {
   Expect.equals(0.0, 0.roundToDouble());
   Expect.equals(1.0, 1.roundToDouble());