using unittest via package import

tests/html/cross_frame_test.dart

 library CrossFrameTest;
-import '../../pkg/unittest/lib/unittest.dart';
-import '../../pkg/unittest/lib/html_config.dart';
+import 'package:unittest/unittest.dart';
+import 'package:unittest/html_config.dart';
 import 'dart:html';
 
 main() {
   useHtmlConfiguration();
 
   var isWindowBase = predicate((x) => x is WindowBase, 'is a WindowBase');
   var isWindow = predicate((x) => x is Window, 'is a Window');
   var isLocationBase = predicate((x) => x is LocationBase, 'is a LocationBase');
   var isLocation =
       predicate((x) => x is Location, 'is a Location');
@@ skipping 52 matching lines @@
 
       // Valid methods.
       frameHistory.forward();
 
       expect(() => frameHistory.length, throws);
 
       final frameParentHistory = iframe.contentWindow.parent.history;
       expect(frameParentHistory, isHistory);
     });
 }