Access BackendUsage through ClosedWorld

pkg/compiler/lib/src/kernel/element_map_impl.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 dart2js.kernel.element_map;
 
 import 'package:kernel/ast.dart' as ir;
 
 import '../common.dart';
 import '../common/names.dart' show Identifiers;
 import '../common/resolution.dart';
 import '../compile_time_constants.dart';
 import '../constants/constant_system.dart';
 import '../constants/constructors.dart';
 import '../constants/evaluation.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/types.dart';
 import '../environment.dart';
 import '../frontend_strategy.dart';
+import '../js_backend/backend_usage.dart';
 import '../js_backend/constant_system_javascript.dart';
 import '../js_backend/interceptor_data.dart';
 import '../js_backend/native_data.dart';
 import '../js_backend/no_such_method_registry.dart';
 import '../native/native.dart' as native;
 import '../native/resolver.dart';
 import '../ordered_typeset.dart';
 import '../ssa/kernel_impact.dart';
 import '../universe/call_structure.dart';
 import '../universe/world_builder.dart';
@@ skipping 1208 matching lines @@
 }
 
 class KernelResolutionWorldBuilder extends KernelResolutionWorldBuilderBase {
   final KernelToElementMapImpl elementMap;
 
   KernelResolutionWorldBuilder(
       this.elementMap,
       NativeBasicData nativeBasicData,
       NativeDataBuilder nativeDataBuilder,
       InterceptorDataBuilder interceptorDataBuilder,
+      BackendUsageBuilder backendUsageBuilder,
       SelectorConstraintsStrategy selectorConstraintsStrategy)
       : super(
             elementMap.elementEnvironment,
             elementMap.commonElements,
             nativeBasicData,
             nativeDataBuilder,
             interceptorDataBuilder,
+            backendUsageBuilder,
             selectorConstraintsStrategy);
 
   @override
   Iterable<InterfaceType> getSupertypes(ClassEntity cls) {
     return elementMap._getOrderedTypeSet(cls).supertypes;
   }
 
   @override
   ClassEntity getSuperClass(ClassEntity cls) {
     return elementMap._getSuperType(cls)?.element;
@@ skipping 91 matching lines @@
     return node.isExternal &&
         !elementMap.isForeignLibrary(node.enclosingLibrary);
   }
 
   @override
   bool isJsInteropMember(MemberEntity element) {
     // TODO(johnniwinther): Compute this.
     return false;
   }
 }