Add a stub implementation of the URLLoaderFactory for AppCache.

content/browser/appcache/appcache_network_service_handler.h

-// Copyright (c) 2017 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_BROWSER_APPCACHE_APPCACHE_NETWORK_SERVICE_HANDLER_
-#define CONTENT_BROWSER_APPCACHE_APPCACHE_NETWORK_SERVICE_HANDLER_
-
-#include <memory>
-
-#include "base/macros.h"
-#include "content/browser/appcache/appcache_service_impl.h"
-#include "content/browser/appcache/appcache_storage.h"
-#include "content/common/content_export.h"
-#include "content/common/url_loader_factory.mojom.h"
-#include "content/public/common/resource_type.h"
-
-namespace content {
-class AppCacheEntry;
-class AppCacheHost;
-class AppCacheNavigationHandleCore;
-class AppCacheStorage;
-class ResourceContext;
-struct ResourceRequest;
-
-// This class is instantiated during navigation, to check if the URL being
-// navigated to can be served out of the AppCache.
-// The AppCacheRequestHandler class provides this functionality as well.
-// However it is tightly coupled with the underlying job and the lifetime
-// of that class gets a touch complicated. The AppCacheRequestHandler is
-// generally associated with a request and it dies when the request goes away.
-// For this case, we are just checking if the URL can be served out of the
-// cache. If yes, then the plan is to create a URLLoaderFactory which can serve
-// URL requests from the cache.
-// TODO(ananta)
-// Look into whether we can get rid of this class when the overall picture of
-// how AppCache interacts with the network service gets clearer.
-class CONTENT_EXPORT AppCacheNetworkServiceHandler
-    : public AppCacheStorage::Delegate {
- public:
-  AppCacheNetworkServiceHandler(
-      std::unique_ptr<ResourceRequest> resource_request,
-      AppCacheNavigationHandleCore* navigation_handle_core,
-      base::Callback<void(mojom::URLLoaderFactoryPtrInfo,
-                          std::unique_ptr<ResourceRequest>)> callback);
-
-  ~AppCacheNetworkServiceHandler() override;
-
-  // Called to start the process of looking up the URL in the AppCache
-  // database,
-  void Start();
-
-  // AppCacheStorage::Delegate methods
-  // The AppCacheNetworkServiceHandler instance is deleted on return from this
-  // function.
-  void OnMainResponseFound(const GURL& url,
-                           const AppCacheEntry& entry,
-                           const GURL& fallback_url,
-                           const AppCacheEntry& fallback_entry,
-                           int64_t cache_id,
-                           int64_t group_id,
-                           const GURL& mainfest_url) override;
-
- private:
-  std::unique_ptr<ResourceRequest> resource_request_;
-
-  // Callback to invoke when we make a determination on whether the request is
-  // to be served from the cache or network.
-  base::Callback<void(mojom::URLLoaderFactoryPtrInfo,
-                      std::unique_ptr<ResourceRequest>)> callback_;
-
-  AppCacheStorage* storage_;
-
-  // The precreated host pointer from the AppCacheNavigationHandleCore class.
-  // The ownership of this pointer stays with the AppCacheNavigationHandleCore
-  // class.
-  AppCacheHost* host_;
-
-  DISALLOW_COPY_AND_ASSIGN(AppCacheNetworkServiceHandler);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_APPCACHE_APPCACHE_NETWORK_SERVICE_HANDLER_