Extract OrderedTypeSetBuilderBase from OrderedTypeSetBuilder

pkg/compiler/lib/src/compiler.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 dart2js.compiler_base;
 
 import 'dart:async' show Future;
 
 import '../compiler_new.dart' as api;
 import 'closure.dart' as closureMapping show ClosureTask;
@@ skipping 1887 matching lines @@
       f(declarer, member);
     }, includeSuperAndInjectedMembers: true);
   }
 
   @override
   ClassEntity getSuperClass(ClassElement cls) => cls.superclass;
 
   @override
   void forEachSupertype(
       ClassElement cls, void f(ResolutionInterfaceType supertype)) {
-    cls.allSupertypes.forEach((ResolutionDartType supertype) => f(supertype));
+    cls.allSupertypes
+        .forEach((ResolutionInterfaceType supertype) => f(supertype));
   }
 
   @override
   void forEachMixin(ClassElement cls, void f(ClassElement mixin)) {
     for (; cls != null; cls = cls.superclass) {
       if (cls.isMixinApplication) {
         MixinApplicationElement mixinApplication = cls;
         f(mixinApplication.mixin);
       }
     }
@@ skipping 82 matching lines @@
   ResolutionFunctionType getLocalFunctionType(LocalFunctionElement function) {
     return function.type;
   }
 
   @override
   ResolutionDartType getUnaliasedType(ResolutionDartType type) {
     type.computeUnaliased(_resolution);
     return type.unaliased;
   }
 }