Revert of Service Worker: Add tests for same-scope new script registration

LayoutTests/http/tests/serviceworker/resources/test-helpers.js

Index: LayoutTests/http/tests/serviceworker/resources/test-helpers.js
diff --git a/LayoutTests/http/tests/serviceworker/resources/test-helpers.js b/LayoutTests/http/tests/serviceworker/resources/test-helpers.js
index f72f60c71e4f53ebbe2332fdc96891d31ada3cf6..6bed2f1460ccb43a2f7b11e2e5749747b113cfbe 100644
--- a/LayoutTests/http/tests/serviceworker/resources/test-helpers.js
+++ b/LayoutTests/http/tests/serviceworker/resources/test-helpers.js
@@ -66,28 +66,18 @@
 }
 
 function wait_for_update(test, registration) {
-  if (!registration || registration.unregister == undefined) {
-    return Promise.reject(new Error(
-      'wait_for_update must be passed a ServiceWorkerRegistration'));
-  }
-
-  return new Promise(test.step_func(function(resolve) {
-      registration.addEventListener('updatefound', test.step_func(function() {
-          resolve(registration.installing);
-      }));
+    return new Promise(test.step_func(function(resolve) {
+        registration.addEventListener('updatefound', test.step_func(function() {
+            resolve(registration.installing);
+        }));
     }));
 }
 
 function wait_for_state(test, worker, state) {
-  if (!worker || worker.state == undefined) {
-    return Promise.reject(new Error(
-      'wait_for_state must be passed a ServiceWorker'));
-  }
-
-  return new Promise(test.step_func(function(resolve) {
-      worker.addEventListener('statechange', test.step_func(function() {
-          if (worker.state === state)
-            resolve(state);
+    return new Promise(test.step_func(function(resolve) {
+        worker.addEventListener('statechange', test.step_func(function() {
+            if (worker.state === state)
+                resolve(state);
         }));
     }));
 }