Add "created-watcher" to the web_components package. This was adapted from

pkg/pkg.status

Index: pkg/pkg.status
diff --git a/pkg/pkg.status b/pkg/pkg.status
index d8666d673e1a4c87cc1fff8de030264392e8588e..32dd8f0e434fa9a83552f149f365622d913eb661 100644
--- a/pkg/pkg.status
+++ b/pkg/pkg.status
@@ -137,7 +137,7 @@ polymer/test/take_attributes_test: Skip #uses dart:html
 polymer/test/template_distribute_dynamic_test: Skip #uses dart:html
 polymer/test/unbind_test: Skip # uses dart:html
 third_party/angular_tests/browser_test: Skip # uses dart:html
-web_components/test/location_wrapper_test: Skip # uses dart:html
+web_components/test/*: Skip # uses dart:html
 
 [$compiler == dart2dart]
 *: Skip