Better mirrors support for mixins and private fields

pkg/dev_compiler/test/codegen/lib/mirrors/private_field_helper.dart

Index: pkg/dev_compiler/test/codegen/lib/mirrors/private_field_helper.dart
diff --git a/pkg/dev_compiler/test/codegen/lib/mirrors/private_field_helper.dart b/pkg/dev_compiler/test/codegen/lib/mirrors/private_field_helper.dart
new file mode 100644
index 0000000000000000000000000000000000000000..8c82450dc84ab269520453f3cea07b2a325ad44e
--- /dev/null
+++ b/pkg/dev_compiler/test/codegen/lib/mirrors/private_field_helper.dart
@@ -0,0 +1,18 @@
+// Copyright (c) 2016, 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 test.mixin;
+
+import 'dart:mirrors';
+
+import 'package:expect/expect.dart';
+
+class Bar {
+  String _field = "hello";
+  String get field => _field;
+}
+
+var privateSymbol2 = #_field;
+var publicSymbol2 = #field;
+