S13nSW: Skip ServiceWorkerTimeoutTimerTest.NonS13nServiceWorker

We should just do early return when S13nServiceWorker is on
because we want to make the flag on by default in the future.

Bug: 860361
Change-Id: I241b491f7f49e47b7cbfa5bfaeb1fab1978442db
Reviewed-on: https://chromium-review.googlesource.com/1143050Reviewed-by: Matt Falkenhagen <falken@chromium.org>
Commit-Queue: Kenichi Ishibashi <bashi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#576389}

content/renderer/service_worker/service_worker_timeout_timer_unittest.cc

@@ -273,7 +273,8 @@ TEST_F(ServiceWorkerTimeoutTimerTest, SetIdleTimerDelayToZero) {
 }
 
 TEST_F(ServiceWorkerTimeoutTimerTest, NonS13nServiceWorker) {
-  ASSERT_FALSE(blink::ServiceWorkerUtils::IsServicificationEnabled());
+  if (blink::ServiceWorkerUtils::IsServicificationEnabled())
+    return;
 
   MockEvent event;
   {