anchor.diff:  // Copyright (c) 2014, 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.
  -
  -// @dart = 2.10
   
   library dart2js.js_emitter.runtime_type_generator;
   
  
positive.code:       // signatures. We either need them for mirrors or because [type] is
        // potentially a subtype of a checked function. Currently we eagerly
        // generate a function type index or signature for all callable classes.
        jsAst.Expression functionTypeIndex;
        bool isDeferred = false;
        if (!type.containsTypeVariables) {
          // TODO(sigmund): use output unit of [method] when the classes mentioned
  
negative.code: 
    void forEachProperty(
        Sorter sorter, void f(jsAst.Name name, jsAst.Node expression)) {
      void handleTypeTest(TypeTest? typeTest) {
        if (typeTest == null) return;
        f(typeTest.name, typeTest.expression);
      }
  
      for (ClassEntity cls in sorter.sortClasses(_properties.keys)) {
        TypeTests typeTests = _properties[cls]!;
        handleTypeTest(typeTests.isTest);
        handleTypeTest(typeTests.substitution);
        handleTypeTest(typeTests.signature);
  