Increase the lifetime of Navigation Preload related objects.

content/renderer/service_worker/service_worker_context_client.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_RENDERER_SERVICE_WORKER_SERVICE_WORKER_CONTEXT_CLIENT_H_
 #define CONTENT_RENDERER_SERVICE_WORKER_SERVICE_WORKER_CONTEXT_CLIENT_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 246 matching lines @@
   void OnNavigateClientResponse(int request_id,
                                 const ServiceWorkerClientInfo& client);
   void OnNavigateClientError(int request_id, const GURL& url);
   void OnDidSkipWaiting(int request_id);
   void OnDidClaimClients(int request_id);
   void OnClaimClientsError(int request_id,
                            blink::WebServiceWorkerError::ErrorType error_type,
                            const base::string16& message);
   void OnPing();
 
+  // Called to resolve the FetchEvent.preloadResponse promise.
   void OnNavigationPreloadResponse(
       int fetch_event_id,
       std::unique_ptr<blink::WebURLResponse> response,
       std::unique_ptr<blink::WebDataConsumerHandle> data_consumer_handle);
+  // Called when the navigation preload request completed. Either
+  // OnNavigationPreloadComplete() or OnNavigationPreloadError() must be called
+  // to release the preload related resources.
+  void OnNavigationPreloadComplete(int fetch_event_id);
+  // Called when an error occured while recieving the response of the navigation

[falken, 2017/01/18 16:32:58]

nit: occurred, receiving

[horo, 2017/01/18 16:52:06]

Done.

+  // preload request.
   void OnNavigationPreloadError(
       int fetch_event_id,
       std::unique_ptr<blink::WebServiceWorkerError> error);
 
   base::WeakPtr<ServiceWorkerContextClient> GetWeakPtr();
 
   const int embedded_worker_id_;
   const int64_t service_worker_version_id_;
   const GURL service_worker_scope_;
   const GURL script_url_;
@@ skipping 15 matching lines @@
   // Initialized on the worker thread in workerContextStarted and
   // destructed on the worker thread in willDestroyWorkerContext.
   std::unique_ptr<WorkerContextData> context_;
 
   DISALLOW_COPY_AND_ASSIGN(ServiceWorkerContextClient);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_SERVICE_WORKER_SERVICE_WORKER_CONTEXT_CLIENT_H_