network service: Create URLLoader for service worker navigation case

content/common/service_worker/service_worker_types.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_COMMON_SERVICE_WORKER_SERVICE_WORKER_TYPES_H_
 #define CONTENT_COMMON_SERVICE_WORKER_SERVICE_WORKER_TYPES_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 265 matching lines @@
 };
 
 struct CONTENT_EXPORT NavigationPreloadState {
   NavigationPreloadState();
   NavigationPreloadState(bool enabled, std::string header);
   NavigationPreloadState(const NavigationPreloadState& other);
   bool enabled;
   std::string header;
 };
 
+struct ResourceRequest;
+using NetworkFallbackCallback =
+    base::Callback<void(std::unique_ptr<ResourceRequest>)>;
+
 }  // namespace content
 
 #endif  // CONTENT_COMMON_SERVICE_WORKER_SERVICE_WORKER_TYPES_H_