Deprecate Math object in corelib in favor of dart:math library.

tests/benchmark_smoke/benchmark_lib.dart

Index: tests/benchmark_smoke/benchmark_lib.dart
diff --git a/tests/benchmark_smoke/benchmark_lib.dart b/tests/benchmark_smoke/benchmark_lib.dart
index 04256192095b5aec68ccd2e49f07e2240853ae2c..0a4c2e56ee5c829fe82f2785d2d1f49169786a77 100644
--- a/tests/benchmark_smoke/benchmark_lib.dart
+++ b/tests/benchmark_smoke/benchmark_lib.dart
@@ -1,4 +1,4 @@
-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// 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.
 
@@ -7,6 +7,7 @@
 #import('dart:coreimpl');
 #import('dart:json');
 #import('dart:html');
+#import('dart:math', prefix: 'Math');
 
 #import('smoketest_lib.dart');
 #source('benchmark_base.dart');