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

lib/compiler/implementation/tree/tree.dart

Index: lib/compiler/implementation/tree/tree.dart
diff --git a/lib/compiler/implementation/tree/tree.dart b/lib/compiler/implementation/tree/tree.dart
index b0786cc9c4190fc494ddf938aded3874a8fb91f2..2e4c5afc0c6b8c61145c81d26a81481e67b8414c 100644
--- a/lib/compiler/implementation/tree/tree.dart
+++ b/lib/compiler/implementation/tree/tree.dart
@@ -1,9 +1,11 @@
-// 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.
 
 #library('tree');
 
+#import('dart:math');
+
 #import('../scanner/scannerlib.dart');
 #import('../util/util.dart');
 #import('../util/characters.dart');