| Index: pkg/compiler/lib/src/js_backend/runtime_types.dart
 | 
| diff --git a/pkg/compiler/lib/src/js_backend/runtime_types.dart b/pkg/compiler/lib/src/js_backend/runtime_types.dart
 | 
| index 21e3e76783e6fc70d4efea0ed572c19ea430d82e..a3692232859185050534cf689e01131d63a7dddb 100644
 | 
| --- a/pkg/compiler/lib/src/js_backend/runtime_types.dart
 | 
| +++ b/pkg/compiler/lib/src/js_backend/runtime_types.dart
 | 
| @@ -227,7 +227,7 @@ class _RuntimeTypes implements RuntimeTypes {
 | 
|        classesNeedingRti.add(cls);
 | 
|  
 | 
|        // TODO(ngeoffray): This should use subclasses, not subtypes.
 | 
| -      compiler.world.forEachStrictSubtypeOf(cls, (ClassElement sub) {
 | 
| +      compiler.closedWorld.forEachStrictSubtypeOf(cls, (ClassElement sub) {
 | 
|          potentiallyAddForRti(sub);
 | 
|        });
 | 
|  
 | 
| 
 |