Bring js_model/model_test on par with compile_from_dill tests.

pkg/compiler/lib/src/universe/resolution_world_builder.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.
 
 part of world_builder;
 
 abstract class ResolutionWorldBuilder implements WorldBuilder, OpenWorld {
   /// Set of all local functions in the program. Used by the mirror tracking
   /// system to find all live closure instances.
   Iterable<Local> get localFunctions;
@@ skipping 910 matching lines @@
     // Use the [:seenClasses:] set to include non-instantiated
     // classes: if the superclass of these classes require RTI, then
     // they also need RTI, so that a constructor passes the type
     // variables to the super constructor.
     forEachInstantiatedClass(addSubtypes);
 
     _classHierarchyNodes.keys.toList().forEach(_ensureClassSet);
 
     return typesImplementedBySubclasses;
   }
+
+  Iterable<MemberEntity> computeAssignedInstanceMembers() {
+    Set<MemberEntity> assignedInstanceMembers = new Set<MemberEntity>();
+    for (MemberEntity instanceMember in _liveInstanceMembers) {
+      if (hasInvokedSetter(instanceMember)) {
+        assignedInstanceMembers.add(instanceMember);
+      }
+    }
+    assignedInstanceMembers.addAll(fieldSetters);
+    return assignedInstanceMembers;
+  }
 }
 
 abstract class KernelResolutionWorldBuilderBase
     extends ResolutionWorldBuilderBase {
   KernelToElementMapForImpactImpl get elementMap;
 
   KernelResolutionWorldBuilderBase(
       ElementEnvironment elementEnvironment,
       DartTypes dartTypes,
       CommonElements commonElements,
@@ skipping 25 matching lines @@
         "ClassHierarchyNode/ClassSet mismatch: "
         "$_classHierarchyNodes vs $_classSets");
     return _closedWorldCache = new KernelClosedWorld(elementMap,
         elementEnvironment: _elementEnvironment,
         dartTypes: _dartTypes,
         commonElements: _commonElements,
         nativeData: _nativeDataBuilder.close(),
         interceptorData: _interceptorDataBuilder.close(),
         backendUsage: _backendUsageBuilder.close(),
         constantSystem: _constantSystem,
-        resolutionWorldBuilder: this,
         implementedClasses: _implementedClasses,
         liveInstanceMembers: _liveInstanceMembers,
+        assignedInstanceMembers: computeAssignedInstanceMembers(),
         allTypedefs: _allTypedefs,
         mixinUses: _mixinUses,
         typesImplementedBySubclasses: typesImplementedBySubclasses,
         classHierarchyNodes: _classHierarchyNodes,
         classSets: _classSets);
   }
 
   @override
   void registerClass(ClassEntity cls) {
     throw new UnimplementedError('KernelResolutionWorldBuilder.registerClass');
   }
 }