Introduced support for external services registration in the ServiceProtocol

runtime/observatory/lib/src/models/objects/service.dart

Index: runtime/observatory/lib/src/models/objects/service.dart
diff --git a/runtime/observatory/lib/src/models/objects/service.dart b/runtime/observatory/lib/src/models/objects/service.dart
new file mode 100644
index 0000000000000000000000000000000000000000..75d7522b05bfa38842205290e26d21f750848bb0
--- /dev/null
+++ b/runtime/observatory/lib/src/models/objects/service.dart
@@ -0,0 +1,9 @@
+// Copyright (c) 2017, 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 models;
+
+abstract class Service {
+  String get alias;
+}