Increase the lifetime of Navigation Preload related objects.

content/renderer/service_worker/service_worker_context_client.cc

Index: content/renderer/service_worker/service_worker_context_client.cc
diff --git a/content/renderer/service_worker/service_worker_context_client.cc b/content/renderer/service_worker/service_worker_context_client.cc
index 4569c4b15c118023841d135470d3d5cf9a0d5b78..1a358ce0e371450bf58e702b643d61f7f1c2e31a 100644
--- a/content/renderer/service_worker/service_worker_context_client.cc
+++ b/content/renderer/service_worker/service_worker_context_client.cc
@@ -267,19 +267,6 @@ class ServiceWorkerContextClient::NavigationPreloadRequest final
         binding_(this, std::move(preload_handle->url_loader_client_request)) {}
 
   ~NavigationPreloadRequest() override {
-    if (result_reported_)
-      return;
-    ServiceWorkerContextClient* client =
-        ServiceWorkerContextClient::ThreadSpecificInstance();
-    if (!client)
-      return;
-    client->OnNavigationPreloadError(
-        fetch_event_id_,
-        base::MakeUnique<blink::WebServiceWorkerError>(
-            blink::WebServiceWorkerError::ErrorTypeAbort,
-            blink::WebString::fromASCII(
-                "Service Worker navigation preload aborted. Need to guard with "
-                "respondWith or waitUntil.")));
   }
 
   void OnReceiveResponse(
@@ -297,8 +284,7 @@ class ServiceWorkerContextClient::NavigationPreloadRequest final
 
   void OnReceiveRedirect(const net::RedirectInfo& redirect_info,
                          const ResourceResponseHead& response_head) override {
-    // Cancel the request.
-    url_loader_ = nullptr;
+    // This will delete itself.

[falken, 2017/01/18 14:24:58]

nit: Slightly prefer |this| instead of "itself"

[horo, 2017/01/18 16:14:57]

Done.

     ReportErrorToClient(
         "Service Worker navigation preload doesn't suport redirect.");
   }
@@ -320,17 +306,21 @@ class ServiceWorkerContextClient::NavigationPreloadRequest final
   }
 
   void OnComplete(const ResourceRequestCompletionStatus& status) override {
-    // We don't report to |client| if OnStartLoadingResponseBody() has already
-    // called OnNavigationPreloadResponse().
-    if (result_reported_)
+    if (status.error_code != net::OK) {
+      ReportErrorToClient("Service Worker navigation preload network error.");

[falken, 2017/01/18 14:24:58]

Does this also delete |this|?

[horo, 2017/01/18 16:14:57]

Done.

+      return;
+    }
+
+    ServiceWorkerContextClient* client =
+        ServiceWorkerContextClient::ThreadSpecificInstance();
+    if (!client)
       return;
-    DCHECK_NE(0, status.error_code);
-    ReportErrorToClient("Service Worker navigation preload network error.");
+    // This will delete itself.
+    client->OnNavigationPreloadComplete(fetch_event_id_);
   }
 
  private:
   void MaybeReportResponseToClient() {
-    DCHECK(!result_reported_);
     if (!response_ || !body_.is_valid())
       return;
     ServiceWorkerContextClient* client =
@@ -341,7 +331,6 @@ class ServiceWorkerContextClient::NavigationPreloadRequest final
     client->OnNavigationPreloadResponse(
         fetch_event_id_, std::move(response_),
         base::MakeUnique<WebDataConsumerHandleImpl>(std::move(body_)));
-    result_reported_ = true;
   }
 
   void ReportErrorToClient(const char* error_message) {
@@ -349,11 +338,11 @@ class ServiceWorkerContextClient::NavigationPreloadRequest final
         ServiceWorkerContextClient::ThreadSpecificInstance();
     if (!client)
       return;
+    // This will delete itself.
     client->OnNavigationPreloadError(
         fetch_event_id_, base::MakeUnique<blink::WebServiceWorkerError>(
                              blink::WebServiceWorkerError::ErrorTypeNetwork,
                              blink::WebString::fromUTF8(error_message)));
-    result_reported_ = true;
   }
 
   const int fetch_event_id_;
@@ -363,7 +352,6 @@ class ServiceWorkerContextClient::NavigationPreloadRequest final
 
   std::unique_ptr<blink::WebURLResponse> response_;
   mojo::ScopedDataPipeConsumerHandle body_;
-  bool result_reported_ = false;
 };
 
 ServiceWorkerContextClient*
@@ -720,12 +708,6 @@ void ServiceWorkerContextClient::didHandleFetchEvent(
     int fetch_event_id,
     blink::WebServiceWorkerEventResult result,
     double event_dispatch_time) {
-  if (context_->preload_requests.Lookup(fetch_event_id)) {
-    // Deletes NavigationPreloadRequest. If the network request is ongoing, it
-    // will be canceled by deleting the mojom::URLLoaderPtr in the
-    // NavigationPreloadRequest.
-    context_->preload_requests.Remove(fetch_event_id);
-  }
   const FetchCallback* callback =
       context_->fetch_event_callbacks.Lookup(fetch_event_id);
   DCHECK(callback);
@@ -1269,6 +1251,12 @@ void ServiceWorkerContextClient::OnNavigationPreloadError(
     int fetch_event_id,
     std::unique_ptr<blink::WebServiceWorkerError> error) {
   proxy_->onNavigationPreloadError(fetch_event_id, std::move(error));
+  context_->preload_requests.Remove(fetch_event_id);
+}
+
+void ServiceWorkerContextClient::OnNavigationPreloadComplete(
+    int fetch_event_id) {
+  context_->preload_requests.Remove(fetch_event_id);

[falken, 2017/01/18 14:24:58]

So either OnError or OnComplete must be called, but not both, right? Could be
worth in the header file.

[horo, 2017/01/18 16:14:57]

Done.

 }
 
 void ServiceWorkerContextClient::BindEventDispatcher(