Refactor VM service IDs

runtime/bin/vmservice/client/lib/src/observatory_elements/function_ref.dart

 // Copyright (c) 2013, 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 canonicalization.b;
+library function_ref_element;
 
 import 'package:polymer/polymer.dart';
-import 'package:canonicalization/c.dart';
-import 'd.dart';
+import 'service_ref.dart';
 
-int b = 0;
-@initMethod _init() {
-  b++;
-  c++;
-  d++;
+@CustomTag('function-ref')
+class FunctionRefElement extends ServiceRefElement {
+  FunctionRefElement.created() : super.created();
 }