fixup! seleniumserver: use managed services in tests

software/seleniumserver/test/test.py

@@ -112,7 +112,7 @@ class WebServerMixin(object):
   """Mixin class which provides a simple web server reachable at self.server_url
   """
   def setUp(self):
-    self.server_url = self.getManagedService('web_server', WebServer)
+    self.server_url = self.getManagedResource('web_server', WebServer).url
 
 
 class BrowserCompatibilityMixin(WebServerMixin):