Remove WorldImpact from caches when no longer needed.

pkg/compiler/lib/src/common/codegen.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.common.codegen;
 
 import '../common.dart';
 import '../compiler.dart' show
     Compiler;
 import '../constants/values.dart' show
@@ skipping 10 matching lines @@
 import '../enqueue.dart' show
     CodegenEnqueuer;
 import '../resolution/tree_elements.dart' show
     TreeElements;
 import '../universe/use.dart' show
     DynamicUse,
     StaticUse,
     TypeUse;
 import '../universe/world_impact.dart' show
     WorldImpact,
-    WorldImpactBuilder;
+    WorldImpactBuilder,
+    WorldImpactVisitor;
 import '../util/util.dart' show
     Pair,
     Setlet;
 import 'registry.dart' show
     Registry,
     EagerRegistry;
 import 'work.dart' show
     ItemCompilationContext,
     WorkItem;
 
@@ skipping 29 matching lines @@
   Setlet<ConstantValue> _compileTimeConstants;
   Setlet<Pair<DartType, DartType>> _typeVariableBoundsSubtypeChecks;
   Setlet<String> _constSymbols;
   List<Set<ClassElement>> _specializedGetInterceptors;
   bool _usesInterceptor = false;
   Setlet<ClassElement> _typeConstants;
   Setlet<FunctionElement> _asyncMarkers;
 
   _CodegenImpact(this.registry);
 
+  void apply(WorldImpactVisitor visitor) {
+    staticUses.forEach(visitor.visitStaticUse);
+    dynamicUses.forEach(visitor.visitDynamicUse);
+    typeUses.forEach(visitor.visitTypeUse);
+  }
+
   void registerCompileTimeConstant(ConstantValue constant) {
     if (_compileTimeConstants == null) {
       _compileTimeConstants = new Setlet<ConstantValue>();
     }
     _compileTimeConstants.add(constant);
   }
 
   Iterable<ConstantValue> get compileTimeConstants {
     return _compileTimeConstants != null
         ? _compileTimeConstants : const <ConstantValue>[];
@@ skipping 164 matching lines @@
       AstElement element,
       ItemCompilationContext compilationContext)
       : super(element, compilationContext);
 
   TreeElements get resolutionTree => element.resolvedAst.elements;
 
   WorldImpact run(Compiler compiler, CodegenEnqueuer world) {
     if (world.isProcessed(element)) return const WorldImpact();
 
     registry = new CodegenRegistry(compiler, element);
-    var impact = compiler.codegen(this, world);
-    compiler.dumpInfoTask.registerImpact(element, impact);
-    return impact;
+    return compiler.codegen(this, world);
   }
 }