Extract OrderedTypeSetBuilderBase from OrderedTypeSetBuilder

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.
 
 library closureToClassMapper;
 
 import 'common/names.dart' show Identifiers;
 import 'common/resolution.dart' show ParsingContext, Resolution;
 import 'common/tasks.dart' show CompilerTask;
 import 'common.dart';
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   @override
   bool get hasConstant => false;
 
   @override
   ConstantExpression get constant => null;
 }
 
 // TODO(ahe): These classes continuously cause problems.  We need to find
 // a more general solution.
 class ClosureClassElement extends ClassElementX {
-  ResolutionDartType rawType;
-  ResolutionDartType thisType;
+  ResolutionInterfaceType rawType;
+  ResolutionInterfaceType thisType;
   ResolutionFunctionType callType;
 
   /// Node that corresponds to this closure, used for source position.
   final FunctionExpression node;
 
   /**
    * The element for the declaration of the function expression.
    */
   final LocalFunctionElement methodElement;
 
@@ skipping 1011 matching lines @@
 ///
 /// Move the below classes to a JS model eventually.
 ///
 abstract class JSEntity implements Entity {
   Entity get declaredEntity;
 }
 
 abstract class PrivatelyNamedJSEntity implements JSEntity {
   Entity get rootOfScope;
 }