No longer store the compilation-context in WorkItem.

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;
 
 import '../compiler_new.dart' as api;
 import 'cache_strategy.dart' show CacheStrategy;
 import 'closure.dart' as closureMapping show ClosureTask;
 import 'common/backend_api.dart' show Backend;
 import 'common/codegen.dart' show CodegenWorkItem;
 import 'common/names.dart' show Selectors;
 import 'common/names.dart' show Identifiers, Uris;
 import 'common/registry.dart' show EagerRegistry, Registry;
 import 'common/resolution.dart'
     show
         ParsingContext,
         Resolution,
         ResolutionWorkItem,
         ResolutionImpact,
         Target;
 import 'common/tasks.dart' show CompilerTask, GenericTask, Measurer;
-import 'common/work.dart' show ItemCompilationContext, WorkItem;
+import 'common/work.dart' show WorkItem;
 import 'common.dart';
 import 'compile_time_constants.dart';
 import 'constants/values.dart';
 import 'core_types.dart' show CoreClasses, CommonElements, CoreTypes;
 import 'dart_types.dart' show DartType, DynamicType, InterfaceType, Types;
 import 'deferred_load.dart' show DeferredLoadTask;
 import 'diagnostics/code_location.dart';
 import 'diagnostics/diagnostic_listener.dart' show DiagnosticReporter;
 import 'diagnostics/invariant.dart' show REPORT_EXCESS_RESOLUTION;
 import 'diagnostics/messages.dart' show Message, MessageTemplate;
@@ skipping 2108 matching lines @@
     }
     _resolutionImpactCache.clear();
   }
 
   @override
   bool hasBeenResolved(Element element) {
     return _worldImpactCache.containsKey(element);
   }
 
   @override
-  ResolutionWorkItem createWorkItem(
-      Element element, ItemCompilationContext compilationContext) {
+  ResolutionWorkItem createWorkItem(Element element) {
     if (compiler.serialization.isDeserialized(element)) {
-      return compiler.serialization
-          .createResolutionWorkItem(element, compilationContext);
+      return compiler.serialization.createResolutionWorkItem(element);
     } else {
-      return new ResolutionWorkItem(element, compilationContext);
+      return new ResolutionWorkItem(element);
     }
   }
 
   @override
   void forgetElement(Element element) {
     _worldImpactCache.remove(element);
     _resolutionImpactCache.remove(element);
   }
 
   ConstantValue _proxyConstant;
@@ skipping 60 matching lines @@
   _ElementScanner(this.scanner);
   void scanLibrary(LibraryElement library) => scanner.scanLibrary(library);
   void scanUnit(CompilationUnitElement unit) => scanner.scan(unit);
 }
 
 class _EmptyEnvironment implements Environment {
   const _EmptyEnvironment();
 
   String valueOf(String key) => null;
 }