Use entities in runtime_types

pkg/compiler/lib/src/js_backend/impact_transformer.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.
 
 library js_backend.backend.impact_transformer;
 
 import '../common.dart';
 import '../common_elements.dart';
 import '../common/backend_api.dart' show ImpactTransformer;
 import '../common/codegen.dart' show CodegenImpact;
 import '../common/resolution.dart' show ResolutionImpact;
 import '../constants/expressions.dart';
 import '../common_elements.dart' show ElementEnvironment;
 import '../elements/elements.dart' show AsyncMarker;
 import '../elements/entities.dart';
 import '../elements/resolution_types.dart' show Types;
 import '../elements/types.dart';
 import '../native/enqueue.dart';
 import '../native/native.dart' as native;
 import '../options.dart';
 import '../universe/feature.dart';
 import '../universe/use.dart'
     show StaticUse, StaticUseKind, TypeUse, TypeUseKind;
 import '../universe/world_impact.dart' show TransformedWorldImpact, WorldImpact;
 import '../util/util.dart';
-import 'backend.dart';
 import 'backend_impact.dart';
 import 'backend_usage.dart';
 import 'checked_mode_helpers.dart';
 import 'custom_elements_analysis.dart';
 import 'interceptor_data.dart';
 import 'lookup_map_analysis.dart';
 import 'mirrors_data.dart';
 import 'namer.dart';
 import 'native_data.dart';
+import 'runtime_types.dart';
 
 class JavaScriptImpactTransformer extends ImpactTransformer {
   final CompilerOptions _options;
   final ElementEnvironment _elementEnvironment;
   final CommonElements _commonElements;
   final BackendImpacts _impacts;
   final NativeBasicData _nativeBasicData;
   final NativeResolutionEnqueuer _nativeResolutionEnqueuer;
   final BackendUsageBuilder _backendUsageBuider;
   final MirrorsDataBuilder _mirrorsDataBuilder;
@@ skipping 421 matching lines @@
           _impacts.asyncStarBody
               .registerImpact(transformed, _elementEnvironment);
           break;
       }
     }
 
     // TODO(johnniwinther): Remove eager registration.
     return transformed;
   }
 }