anchor.diff:              checkedClass, _namer.operatorIs(checkedClass), js('1'));
         }
         Substitution substitution = check.substitution;
  -      if (substitution != null) {
  +      if (substitution != null && !_options.experimentNewRti) {
           jsAst.Expression body =
               _getSubstitutionCode(emitterTask.emitter, substitution);
           result.addSubstitution(
  
positive.code:   final RuntimeTypesChecks _rtiChecks;
    final RuntimeTypesEncoder _rtiEncoder;
    final _TypeContainedInOutputUnitVisitor _outputUnitVisitor;
  
    RuntimeTypeGenerator(this._commonElements, this._outputUnitData,
        this.emitterTask, this._namer, this._rtiChecks, this._rtiEncoder)
  
negative.code: import '../js_backend/runtime_types_codegen.dart'
      show ClassChecks, ClassFunctionType, Substitution, TypeCheck;
  import '../js_emitter/sorter.dart';
  import '../options.dart';
  import '../util/util.dart' show Setlet;
  
  import 'code_emitter_task.dart' show CodeEmitterTask, Emitter;
  