Handle variable declarations in inferrer

pkg/compiler/lib/src/kernel/indexed.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.
 
 /// Indexed entity interfaces for modeling elements derived from Kernel IR.
 
 import '../elements/entities.dart';
 
 abstract class _Indexed {
   int _index;
@@ skipping 26 matching lines @@
     implements TypeVariableEntity {
   /// Type variable index used for fast lookup in [KernelToElementMapBase].
   int get typeVariableIndex => _index;
 }
 
 abstract class IndexedTypedef extends _Indexed implements TypedefEntity {
   /// Typedef index used for fast lookup in [KernelToElementMapBase].
   int get typedefIndex => _index;
 }
 
+abstract class IndexedLocal extends _Indexed implements Local {
+  int get localIndex => _index;
+}
+
 /// Base implementation for an index based map of entities of type [E].
 abstract class EntityMapBase<E extends _Indexed> {
   List<E> _list = <E>[];
 
   /// Returns the [index]th entity in the map.
   E getEntity(int index) => _list[index];
 
   /// Returns the number entities in the map.
   int get length => _list.length;
 }
@@ skipping 81 matching lines @@
     assert(entity._index == null);
     entity._index = _list.length;
     _list.add(entity);
     assert(data != null);
     _data.add(data);
     assert(env != null);
     _env.add(env);
     return entity;
   }
 }