Correctly handle setters in KernelWorldBuilder

tests/compiler/dart2js/kernel/closed_world2_test.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.
 
 // Partial test that the closed world computed from [WorldImpact]s derived from
 // kernel is equivalent to the original computed from resolution.
 library dart2js.kernel.closed_world2_test;
 
 import 'package:async_helper/async_helper.dart';
 import 'package:compiler/src/closure.dart';
@@ skipping 108 matching lines @@
             worldBuilder.elementEnvironment,
             worldBuilder.commonElements,
             nativeBasicData,
             const OpenWorldStrategy()),
         new KernelWorkItemBuilder(worldBuilder, impactTransformer),
         'enqueuer from kelements');
     computeClosedWorld(
         compiler.reporter, enqueuer2, worldBuilder.elementEnvironment);
     BackendUsage backendUsage2 = backendUsageBuilder2.close();
     checkBackendUsage(backendUsage1, backendUsage2, equivalence);
+
+    checkResolutionEnqueuers(backendUsage1, backendUsage2, enqueuer1, enqueuer2,
+        elementEquivalence: equivalence.entityEquivalence,
+        typeEquivalence: (ResolutionDartType a, DartType b) {
+      return equivalence.typeEquivalence(unalias(a), b);
+    }, elementFilter: elementFilter, verbose: arguments.verbose);
   });
 }
 
 List createKernelResolutionEnqueuerListener(
     CompilerOptions options,
     DiagnosticReporter reporter,
     DeferredLoadTask deferredLoadTask,
     KernelWorldBuilder worldBuilder,
     NativeBasicData nativeBasicData) {
   ElementEnvironment elementEnvironment = worldBuilder.elementEnvironment;
@@ skipping 219 matching lines @@
       usage2.isInvokeOnUsed);
   check(usage1, usage2, 'isRuntimeTypeUsed', usage1.isRuntimeTypeUsed,
       usage2.isRuntimeTypeUsed);
   check(usage1, usage2, 'isIsolateInUse', usage1.isIsolateInUse,
       usage2.isIsolateInUse);
   check(usage1, usage2, 'isFunctionApplyUsed', usage1.isFunctionApplyUsed,
       usage2.isFunctionApplyUsed);
   check(usage1, usage2, 'isNoSuchMethodUsed', usage1.isNoSuchMethodUsed,
       usage2.isNoSuchMethodUsed);
 }