Create closed world for hello world using .dill file

pkg/compiler/lib/src/kernel/element_map.dart

 // 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.
 
 import 'package:kernel/ast.dart' as ir;
 
 import '../common.dart';
 import '../common/names.dart';
 import '../constants/constructors.dart';
 import '../constants/expressions.dart';
 import '../constants/values.dart';
 import '../common_elements.dart';
-import '../elements/elements.dart';
 import '../elements/entities.dart';
 import '../elements/names.dart';
 import '../elements/operators.dart';
 import '../elements/types.dart';
 import '../js_backend/backend.dart' show JavaScriptBackend;
 import '../native/native.dart' as native;
 import '../universe/call_structure.dart';
 import '../universe/selector.dart';
 import 'kernel_debug.dart';
 
@@ skipping 143 matching lines @@
     }
     throw new SpannableAssertionFailure(
         CURRENT_ELEMENT_SPANNABLE,
         "Can only get the selector for a property get or an invocation: "
         "${node}");
   }
 
   Selector getInvocationSelector(ir.InvocationExpression invocation) {
     Name name = getName(invocation.name);
     SelectorKind kind;
-    if (Elements.isOperatorName(invocation.name.name)) {
+    if (Selector.isOperatorName(name.text)) {
       if (name == Names.INDEX_NAME || name == Names.INDEX_SET_NAME) {
         kind = SelectorKind.INDEX;
       } else {
         kind = SelectorKind.OPERATOR;
       }
     } else {
       kind = SelectorKind.CALL;
     }
 
     CallStructure callStructure = getCallStructure(invocation.arguments);
@@ skipping 627 matching lines @@
     }
     if (isRedirecting) {
       return new RedirectingGenerativeConstantConstructor(
           defaultValues, superConstructorInvocation);
     } else {
       return new GenerativeConstantConstructor(
           type, defaultValues, fieldMap, superConstructorInvocation);
     }
   }
 }