Remove Enqueuer argument from Backend.registerStaticUse

pkg/compiler/lib/src/js_backend/type_variable_handler.dart

 // Copyright (c) 2013, 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.
 
 import '../common.dart';
 import '../common/registry.dart' show Registry;
 import '../compiler.dart' show Compiler;
 import '../constants/expressions.dart';
 import '../constants/values.dart';
 import '../dart_types.dart';
@@ skipping 39 matching lines @@
   final StagedWorldImpactBuilder impactBuilder = new StagedWorldImpactBuilder();
 
   TypeVariableHandler(this._compiler);
 
   ClassElement get _typeVariableClass => _backend.helpers.typeVariableClass;
   CodeEmitterTask get _task => _backend.emitter;
   MetadataCollector get _metadataCollector => _task.metadataCollector;
   JavaScriptBackend get _backend => _compiler.backend;
   DiagnosticReporter get reporter => _compiler.reporter;
 
-  void onQueueEmpty(Enqueuer enqueuer) {
-    if (enqueuer.isResolutionQueue) return;
-
-    enqueuer.applyImpact(null, impactBuilder.flush());
+  /// Compute the [WorldImpact] for the type variables registered since last
+  /// flush.
+  WorldImpact flush({bool forResolution}) {
+    if (forResolution) return const WorldImpact();
+    return impactBuilder.flush();
   }
 
   void registerClassWithTypeVariables(
       ClassElement cls, Enqueuer enqueuer, Registry registry) {
     if (enqueuer.isResolutionQueue) {
       // On first encounter, we have to ensure that the support classes get
       // resolved.
       if (!_seenClassesWithTypeVariables) {
         _backend.enqueueClass(enqueuer, _typeVariableClass, registry);
         _typeVariableClass.ensureResolved(_compiler.resolution);
@@ skipping 94 matching lines @@
   }
 
   List<jsAst.Expression> typeVariablesOf(ClassElement classElement) {
     List<jsAst.Expression> result = _typeVariables[classElement];
     if (result == null) {
       result = const <jsAst.Expression>[];
     }
     return result;
   }
 }