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pkg/compiler/lib/src/kernel/kernel_backend_strategy.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.backend_strategy;
 
 import 'package:kernel/ast.dart' as ir;
 
 import '../backend_strategy.dart';
 import '../closure.dart';
 import '../common/codegen.dart' show CodegenRegistry, CodegenWorkItem;
 import '../common/tasks.dart';
 import '../compiler.dart';
 import '../elements/entities.dart';
 import '../enqueue.dart';
 import '../io/source_information.dart';
+import '../js/js_source_mapping.dart';
 import '../js_backend/backend.dart';
 import '../js_backend/native_data.dart';
 import '../js_emitter/sorter.dart';
 import '../kernel/element_map.dart';
 import '../kernel/element_map_impl.dart';
 import '../native/behavior.dart';
 import '../ssa/builder_kernel.dart';
 import '../ssa/nodes.dart';
 import '../ssa/ssa.dart';
 import '../ssa/types.dart';
@@ skipping 42 matching lines @@
   }
 
   @override
   SsaBuilderTask createSsaBuilderTask(JavaScriptBackend backend,
       SourceInformationStrategy sourceInformationStrategy) {
     return new KernelSsaBuilderTask(backend.compiler);
   }
 
   @override
   SourceInformationStrategy get sourceInformationStrategy =>
-      const SourceInformationStrategy();
+      const JavaScriptSourceInformationStrategy();
 }
 
 class KernelCodegenWorkItemBuilder implements WorkItemBuilder {
   final JavaScriptBackend _backend;
   final ClosedWorld _closedWorld;
 
   KernelCodegenWorkItemBuilder(this._backend, this._closedWorld);
 
   @override
   CodegenWorkItem createWorkItem(MemberEntity entity) {
@@ skipping 129 matching lines @@
   @override
   ClosureClassMap getLocalFunctionMap(Local localFunction) {
     return new ClosureClassMap(null, null, null, null);
   }
 
   @override
   ClosureClassMap getMemberMap(MemberEntity member) {
     return new ClosureClassMap(null, null, null, null);
   }
 }