add @MirrorsUsed to observe/polymer/polymer_exprs pkgs

pkg/polymer_expressions/lib/eval.dart

 // 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.
 
 library polymer_expressions.eval;
 
 import 'dart:async';
 import 'dart:collection';
+
+@MirrorsUsed(metaTargets: const [Reflectable, ObservableProperty],
+    override: 'polymer_expressions.eval')

[Siggi Cherem (dart-lang), 2013/10/15 21:52:18]

ditto

[Jennifer Messerly, 2013/10/15 22:03:29]

ditto :)

 import 'dart:mirrors';
 
 import 'package:observe/observe.dart';
 
 import 'async.dart';
 import 'expression.dart';
 import 'filter.dart';
 import 'visitor.dart';
 import 'src/mirrors.dart';
 
@@ skipping 622 matching lines @@
    * This does not work for calls that need to pass more than one argument.
    */
   call(arg0) => mirror.invoke(symbol, [arg0], null).reflectee;
 }
 
 class EvalException implements Exception {
   final String message;
   EvalException(this.message);
   String toString() => "EvalException: $message";
 }