Mirrors overhaul.

dart/runtime/lib/mirrors_patch.dart

 // 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.
 
 import "dart:nativewrappers";
 // TODO(ahe): Move _symbol_dev.Symbol to its own "private" library?
 import "dart:_collection-dev" as _symbol_dev;
 
 /**
  * Returns a [MirrorSystem] for the current isolate.
@@ skipping 47 matching lines @@
     }
     if (library != null) name = _mangleName(name, library._reflectee);
     return new _symbol_dev.Symbol.unvalidated(name);
   }
 
   static _unmangleName(String name)
       native "Mirrors_unmangleName";
   static _mangleName(String name, _MirrorReference lib)
       native "Mirrors_mangleName";
 }
+
+// TODO(rmacnak): Eliminate this class.
+class MirroredCompilationError {
+  final String message;
+
+  MirroredCompilationError(this.message);
+
+  String toString() {
+    return "Compile-time error during mirrored execution: <$message>";
+  }
+}