Use JS backend in serialization_analysis_test

pkg/compiler/lib/src/compiler.dart

 // Copyright (c) 2012, 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.compiler_base;
 
 import 'dart:async' show
     EventSink,
     Future;
 
@@ skipping 16 matching lines @@
     Registry;
 import 'common/resolution.dart' show
     Parsing,
     Resolution,
     ResolutionWorkItem,
     ResolutionImpact;
 import 'common/tasks.dart' show
     CompilerTask,
     GenericTask;
 import 'common/work.dart' show
+    ItemCompilationContext,
     WorkItem;
 import 'compile_time_constants.dart';
 import 'constants/values.dart';
 import 'core_types.dart' show
     CoreClasses,
     CoreTypes;
 import 'dart_backend/dart_backend.dart' as dart_backend;
 import 'dart_types.dart' show
     DartType,
     DynamicType,
@@ skipping 2087 matching lines @@
       }
       WorldImpact worldImpact =
           compiler.backend.impactTransformer.transformResolutionImpact(
               resolutionImpact);
       return worldImpact;
     });
   }
 
   @override
   void uncacheWorldImpact(Element element) {
+    if (compiler.serialization.isDeserialized(element)) return;
     assert(invariant(element, _worldImpactCache[element] != null,
         message: "WorldImpact not computed for $element."));
     _worldImpactCache[element] = const WorldImpact();
   }
 
   @override
   void emptyCache() {
     for (Element element in _worldImpactCache.keys) {
       _worldImpactCache[element] = const WorldImpact();
     }
   }
 
   @override
   bool hasBeenResolved(Element element) {
     return _worldImpactCache.containsKey(element);
   }
+
+  @override
+  ResolutionWorkItem createWorkItem(
+      Element element, ItemCompilationContext compilationContext) {
+    if (compiler.serialization.isDeserialized(element)) {
+      return compiler.serialization.createResolutionWorkItem(
+          element, compilationContext);
+    } else {
+      return new ResolutionWorkItem(element, compilationContext);
+    }
+  }
 }
 
 // TODO(johnniwinther): Move [ParserTask], [PatchParserTask], [DietParserTask]
 // and [ScannerTask] here.
 class _CompilerParsing implements Parsing {
   final Compiler compiler;
 
   _CompilerParsing(this.compiler);
 
   @override
@@ skipping 33 matching lines @@
     if (_otherDependencies == null) {
       _otherDependencies = new Setlet<Element>();
     }
     _otherDependencies.add(element.implementation);
   }
 
   Iterable<Element> get otherDependencies {
     return _otherDependencies != null ? _otherDependencies : const <Element>[];
   }
 }