using unittest via package import

tests/html/isolates_test.dart

 library IsolatesTest;
-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:async';
 import 'dart:html';
 import 'dart:convert';
 import 'dart:isolate' as isolate;
 
 String responseFor(message) => 'response for $message';
 
 void isolateEntry(isolate.SendPort initialReplyTo) {
   var port = new isolate.ReceivePort();
   initialReplyTo.send(port.sendPort);
@@ skipping 42 matching lines @@
       sendReceive(port, msg1).then((response) {
         expect(response, equals(responseFor(msg1)));
         sendReceive(port, msg2).then((response) {
           expect(response, equals(responseFor(msg2)));
           callback();
         });
       });
     });
   });
 }