anchor.diff:    final RuntimeTypesChecks _rtiChecks;
     final RuntimeTypesEncoder _rtiEncoder;
     final _TypeContainedInOutputUnitVisitor _outputUnitVisitor;
  +
  +  CompilerOptions get _options => emitterTask.options;
   
     RuntimeTypeGenerator(this._commonElements, this._outputUnitData,
         this.emitterTask, this._namer, this._rtiChecks, this._rtiEncoder)
  
positive.code:             checkedClass, _namer.operatorIs(checkedClass), js('1'));
        }
        Substitution substitution = check.substitution;
        if (substitution != null) {
          jsAst.Expression body =
              _getSubstitutionCode(emitterTask.emitter, substitution);
          result.addSubstitution(
  
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;
  