Implement updateViaCache flag and no-cache by default for main service worker scripts

content/child/service_worker/web_service_worker_registration_impl.cc

Index: content/child/service_worker/web_service_worker_registration_impl.cc
diff --git a/content/child/service_worker/web_service_worker_registration_impl.cc b/content/child/service_worker/web_service_worker_registration_impl.cc
index de0acf7b035d155c5c01d7e96c9c565576c40cfb..ed1471a356cb07ba3ab018340f813a6d36c1fc8b 100644
--- a/content/child/service_worker/web_service_worker_registration_impl.cc
+++ b/content/child/service_worker/web_service_worker_registration_impl.cc
@@ -123,6 +123,10 @@ blink::WebURL WebServiceWorkerRegistrationImpl::scope() const {
   return handle_ref_->scope();
 }
 
+bool WebServiceWorkerRegistrationImpl::useCache() const {
+  return handle_ref_->use_cache();
+}
+
 void WebServiceWorkerRegistrationImpl::update(
     blink::WebServiceWorkerProvider* provider,
     std::unique_ptr<WebServiceWorkerUpdateCallbacks> callbacks) {