Wrapping leaf nodes in non polymer elements

runtime/observatory/lib/src/mocks/exceptions/connection_exception.dart

Index: runtime/observatory/lib/src/mocks/exceptions/connection_exception.dart
diff --git a/runtime/observatory/lib/src/mocks/exceptions/connection_exception.dart b/runtime/observatory/lib/src/mocks/exceptions/connection_exception.dart
new file mode 100644
index 0000000000000000000000000000000000000000..03d2629825699bf3bacb42f77f9b3612a1fbe620
--- /dev/null
+++ b/runtime/observatory/lib/src/mocks/exceptions/connection_exception.dart
@@ -0,0 +1,11 @@
+// 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
+
+part of mocks;
+
+class ConnectionExceptionMock implements M.ConnectionException {
+  final String message;
+
+  ConnectionExceptionMock(this.message);
+}