[WIP] [service worker] Fix detach controller and fallback to network mechanism

content/browser/service_worker/service_worker_url_request_job.cc

Index: content/browser/service_worker/service_worker_url_request_job.cc
diff --git a/content/browser/service_worker/service_worker_url_request_job.cc b/content/browser/service_worker/service_worker_url_request_job.cc
index 143e354e8b14345bb27ea9a028e9888ada8892d6..8e7c0bf3ca10829c9bebe866fccafa58a529e20c 100644
--- a/content/browser/service_worker/service_worker_url_request_job.cc
+++ b/content/browser/service_worker/service_worker_url_request_job.cc
@@ -586,8 +586,10 @@ void ServiceWorkerURLRequestJob::DidDispatchFetchEvent(
       // Using the service worker failed, so fallback to network. Detach the
       // controller so subresource requests also skip the worker.
       provider_host_->NotifyControllerLost();
-      response_type_ = FALLBACK_TO_NETWORK;
-      NotifyRestartRequired();
+      fall_back_required_ = true;
+      CreateResponseHeader(400, "Service Worker Fallback Required",
+                           ServiceWorkerHeaderMap());
+      CommitResponseHeader();
     } else {
       DeliverErrorResponse();
     }