anchor.diff:    expectInstance(res, InstanceKind.kDouble, DateTime.now().year.toString());
   }
   
  +Future<void> evaluateWebLibraryBooleanFromEnvironmentInLibrary(FlutterTestDriver flutter) async {
  +  final LibraryRef library = await getRootLibrary(flutter);
  +  final ObjRef res = await flutter.evaluate(library.id, 'const bool.fromEnvironment("dart.library.html")');
  +  expectInstance(res, InstanceKind.kBool, true.toString());
  +}
  +
   Future<LibraryRef> getRootLibrary(FlutterTestDriver flutter) async {
     // `isolate.rootLib` returns incorrect library, so find the
     // entrypoint manually here instead.
  
positive.code:       await startPaused(expressionEvaluation: true);
        await evaluateComplexExpressionsInLibrary(flutter);
      });
    });
  }
  
  
negative.code:     testWithoutContext('can evaluate complex expressions in library without pause', () async {
        await start(expressionEvaluation: true);
        await evaluateComplexExpressionsInLibrary(flutter);
      });
  
      testWithoutContext('evaluated expression includes web library environment defines', () async {
        await start(expressionEvaluation: true);
        await evaluateWebLibraryBooleanFromEnvironmentInLibrary(flutter);
      });
    });
  
  