Hopefully the last bit of restructuring between closture classes and loop boxing, etc.

pkg/compiler/lib/src/kernel/element_map.dart

 // Copyright (c) 2017, 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 'package:js_runtime/shared/embedded_names.dart';
 import 'package:kernel/ast.dart' as ir;
 
 import '../closure.dart';
 import '../common.dart';
 import '../common/names.dart';
@@ skipping 1061 matching lines @@
   /// Call to notify that [member] is no longer being inlined.
   void leaveInlinedMember(covariant MemberEntity member);
 
   /// Returns the [Local] for [node].
   Local getLocal(ir.VariableDeclaration node);
 
   /// Returns the [JumpTarget] for the branch in [node].
   // TODO(johnniwinther): Split this by kind of [node]?
   JumpTarget getJumpTarget(ir.TreeNode node, {bool isContinueTarget: false});
 
-  /// Returns the [LoopClosureRepresentationInfo] for the loop [node] in
-  /// [closureClassMaps].
-  LoopClosureRepresentationInfo getClosureRepresentationInfoForLoop(
+  /// Returns the [ClosureBase] for the loop [node] in [closureClassMaps].
+  ClosureBase getClosureRepresentationInfoForLoop(
       ClosureDataLookup closureLookup, ir.TreeNode node);
 }
 
 /// Comparator for the canonical order or named arguments.
 // TODO(johnniwinther): Remove this when named parameters are sorted in dill.
 int namedOrdering(ir.VariableDeclaration a, ir.VariableDeclaration b) {
   return a.name.compareTo(b.name);
 }