Make compile-time errors catchable

runtime/lib/errors_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:_internal' as internal;
 import 'dart:convert' show JSON;
 
 @patch class Error {
   @patch static String _objectToString(Object object) {
     return Object._toString(object);
@@ skipping 340 matching lines @@
       msg_buf.write(
           "NoSuchMethodError: incorrect number of arguments passed to "
           "method named '$memberName'\n"
           "Receiver: $receiver_str\n"
           "Tried calling: $memberName($actualParameters)\n"
           "Found: $memberName($formalParameters)");
     }
     return msg_buf.toString();
   }
 }
+
+
+class _CompileTimeError extends Error {
+  final String _errorMsg;
+  _CompileTimeError(this._errorMsg);
+  String toString() => _errorMsg;
+}