Modify backend strategy and how we access the closure converter.

pkg/compiler/lib/src/closure.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.
 
 import 'common/names.dart' show Identifiers;
 import 'common/resolution.dart' show ParsingContext, Resolution;
-import 'common/tasks.dart' show CompilerTask;
+import 'common/tasks.dart' show CompilerTask, Measurer;
 import 'common.dart';
 import 'compiler.dart' show Compiler;
 import 'constants/expressions.dart';
 import 'elements/elements.dart';
 import 'elements/entities.dart';
 import 'elements/entity_utils.dart' as utils;
 import 'elements/modelx.dart'
     show BaseFunctionElementX, ClassElementX, ElementX;
 import 'elements/resolution_types.dart';
 import 'elements/types.dart';
 import 'elements/visitor.dart' show ElementVisitor;
 import 'js_backend/js_backend.dart' show JavaScriptBackend;
 import 'resolution/tree_elements.dart' show TreeElements;
 import 'package:front_end/src/fasta/scanner.dart' show Token;
 import 'tree/tree.dart';
 import 'util/util.dart';
 import 'world.dart' show ClosedWorldRefiner;
 
+abstract class ClosureConversionTask<T> extends CompilerTask
+    implements ClosureDataLookup<T> {
+  ClosureConversionTask(Measurer measurer) : super(measurer);
+
+  //void analyzeClosures();
+  void convertClosures(Iterable<MemberEntity> processedEntities,
+      ClosedWorldRefiner closedWorldRefiner);
+}
+
 /// Class that provides information for how closures are rewritten/represented
 /// to preserve Dart semantics when compiled to JavaScript. Given a particular
 /// node to look up, it returns a information about the internal representation
 /// of how closure conversion is implemented. T is an ir.Node or Node.
 abstract class ClosureDataLookup<T> {
   /// Look up information about the variables that have been mutated and are
   /// used inside the scope of [node].
   // TODO(johnniwinther): Split this up into two functions, one for members and
   // one for local functions.
   ClosureRepresentationInfo getClosureRepresentationInfo(Entity member);
@@ skipping 155 matching lines @@
   /// Return true if [variable] has been captured and mutated (all other
   /// variables do not require boxing).
   bool isVariableBoxed(Local variable) => false;
 
   // TODO(efortuna): Remove this method. The old system was using
   // ClosureClassMaps for situations other than closure class maps, and that's
   // just confusing.
   bool get isClosure => false;
 }
 
-class ClosureTask extends CompilerTask implements ClosureDataLookup<Node> {
+class ClosureTask extends ClosureConversionTask<Node> {
   Map<Node, ClosureScope> _closureInfoMap = <Node, ClosureScope>{};
   Map<Element, ClosureClassMap> _closureMappingCache =
       <Element, ClosureClassMap>{};
   Compiler compiler;
   ClosureTask(Compiler compiler)
       : compiler = compiler,
         super(compiler.measurer);
 
   String get name => "Closure Simplifier";
 
   DiagnosticReporter get reporter => compiler.reporter;
 
+  void convertClosures(Iterable<MemberEntity> processedEntities,
+      ClosedWorldRefiner closedWorldRefiner) {
+    createClosureClasses(closedWorldRefiner);
+  }
+
   ClosureAnalysisInfo getClosureAnalysisInfo(Node node) {
     var value = _closureInfoMap[node];
     return value == null ? const ClosureAnalysisInfo() : value;
   }
 
   ClosureRepresentationInfo getClosureRepresentationInfo(Element member) {
     return getClosureToClassMapping(member);
   }
 
   LoopClosureRepresentationInfo getClosureRepresentationInfoForLoop(
@@ skipping 1224 matching lines @@
 ///
 /// Move the below classes to a JS model eventually.
 ///
 abstract class JSEntity implements MemberEntity {
   Local get declaredEntity;
 }
 
 abstract class PrivatelyNamedJSEntity implements JSEntity {
   Entity get rootOfScope;
 }