ServiceWorker: Enable ServiceWorkerRegistration and update layout tests

LayoutTests/http/tests/serviceworker/unregister-controller.html

Index: LayoutTests/http/tests/serviceworker/unregister-controller.html
diff --git a/LayoutTests/http/tests/serviceworker/unregister-controller.html b/LayoutTests/http/tests/serviceworker/unregister-controller.html
index 4939a3c29c4de40a316f7d25b64e380e414d5934..210b8d3dfa2dbced36574d1b3c91a7c5027c6e3d 100644
--- a/LayoutTests/http/tests/serviceworker/unregister-controller.html
+++ b/LayoutTests/http/tests/serviceworker/unregister-controller.html
@@ -13,6 +13,9 @@ async_test(function(t) {
   var controller;
 
   service_worker_unregister_and_register(t, worker_url, scope)
+    .then(function(registration) {
+        return wait_for_update(t, registration);
+      })
     .then(function(registered_worker) {
         worker = registered_worker;
         return wait_for_state(t, worker, 'activated');
@@ -39,13 +42,16 @@ async_test(function(t) {
         t.done();
       })
     .catch(unreached_rejection(t));
-}, 'Unregister does not affect existing controller');
+  }, 'Unregister does not affect existing controller');
 
 async_test(function(t) {
   var scope =
       'resources/unregister-controller-page.html?load-after-unregister';
 
   service_worker_unregister_and_register(t, worker_url, scope)
+    .then(function(registration) {
+      return wait_for_update(t, registration);
+    })
     .then(function(worker) {
         return wait_for_state(t, worker, 'activated');
       })
@@ -67,5 +73,5 @@ async_test(function(t) {
         t.done();
       })
     .catch(unreached_rejection(t));
-}, 'Unregister prevents control of subsequent navigations');
+  }, 'Unregister prevents control of subsequent navigations');
 </script>