Rename ClosureClassMaps to ClosureDataLookup

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:kernel/ast.dart' as ir;
 
 import '../closure.dart';
 import '../common.dart';
 import '../common/names.dart';
 import '../constants/constructors.dart';
@@ skipping 1024 matching lines @@
   /// 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(
-      ClosureClassMaps closureClassMaps, ir.TreeNode node);
+      ClosureDataLookup closureLookup, ir.TreeNode node);
 }