ServiceWorker: Bypass SW when the script doesn't have fetch handler

content/browser/service_worker/service_worker_controllee_request_handler.cc

Index: content/browser/service_worker/service_worker_controllee_request_handler.cc
diff --git a/content/browser/service_worker/service_worker_controllee_request_handler.cc b/content/browser/service_worker/service_worker_controllee_request_handler.cc
index 7b9b35c2f65f13ebd0b38aab55b6107763f09df3..9d171c37a08584c514cb72c13c743f7a225e4c11 100644
--- a/content/browser/service_worker/service_worker_controllee_request_handler.cc
+++ b/content/browser/service_worker/service_worker_controllee_request_handler.cc
@@ -26,6 +26,20 @@
 
 namespace content {
 
+namespace {
+
+void MaybeForwardToServiceWorker(ServiceWorkerURLRequestJob* job,
+                                 ServiceWorkerVersion* version) {
+  DCHECK(job);
+  DCHECK(version);
+  if (version->has_fetch_handler())
+    job->ForwardToServiceWorker();
+  else
+    job->FallbackToNetwork();
+}
+
+}  // namespace
+
 ServiceWorkerControlleeRequestHandler::ServiceWorkerControlleeRequestHandler(
     base::WeakPtr<ServiceWorkerContextCore> context,
     base::WeakPtr<ServiceWorkerProviderHost> provider_host,
@@ -251,8 +265,8 @@ ServiceWorkerControlleeRequestHandler::DidLookupRegistrationForMainResource(
   }
 
   ServiceWorkerMetrics::CountControlledPageLoad(stripped_url_);
+  MaybeForwardToServiceWorker(job_.get(), active_version.get());
 
-  job_->ForwardToServiceWorker();
   TRACE_EVENT_ASYNC_END2(
       "ServiceWorker",
       "ServiceWorkerControlleeRequestHandler::PrepareForMainResource",
@@ -282,7 +296,8 @@ void ServiceWorkerControlleeRequestHandler::OnVersionStatusChanged(
 
   provider_host_->AssociateRegistration(registration,
                                         false /* notify_controllerchange */);
-  job_->ForwardToServiceWorker();
+
+  MaybeForwardToServiceWorker(job_.get(), version);
 }
 
 void ServiceWorkerControlleeRequestHandler::DidUpdateRegistration(
@@ -352,7 +367,7 @@ void ServiceWorkerControlleeRequestHandler::PrepareForSubResource() {
   DCHECK(job_.get());
   DCHECK(context_);
   DCHECK(provider_host_->active_version());
-  job_->ForwardToServiceWorker();
+  MaybeForwardToServiceWorker(job_.get(), provider_host_->active_version());
 }
 
 void ServiceWorkerControlleeRequestHandler::OnPrepareToRestart() {