Converted Observatory refs elements

runtime/observatory/tests/observatory_ui/mocks/objects/script.dart

 // 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 ScriptRefMock implements M.ScriptRef {
   final String id;
   final String uri;
 
   const ScriptRefMock({this.id, this.uri});
 }
 
 typedef int TokenToInt(int token);
 
 class ScriptMock implements M.Script {
   final String id;
+  final M.ClassRef clazz;
   final int size;
   final String uri;
   final String source;
 
   final TokenToInt _tokenToLine;
   final TokenToInt _tokenToCol;
 
   int tokenToLine(int token) => _tokenToLine(token);
   int tokenToCol(int token) => _tokenToCol(token);
 
-  const ScriptMock({this.id, this.size, this.uri, this.source,
+  const ScriptMock({this.id, this.clazz, this.size, this.uri, this.source,
       TokenToInt tokenToLine, TokenToInt tokenToCol})
     : _tokenToLine = tokenToLine,
       _tokenToCol = tokenToCol;
 }