Add a stub implementation of the URLLoaderFactory for AppCache.

content/browser/appcache/appcache_url_loader_factory.h

+// Copyright 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_URL_LOADER_FACTORY_H_
+#define CONTENT_BROWSER_APPCACHE_APPCACHE_URL_LOADER_FACTORY_H_
+
+#include "base/memory/ref_counted.h"
+#include "content/common/url_loader_factory.mojom.h"
+#include "mojo/public/cpp/bindings/strong_binding_set.h"
+#include "url/gurl.h"
+
+namespace content {
+class ChromeAppCacheService;
+class URLLoaderFactoryGetter;
+
+// Implements the URLLoaderFactory mojom for AppCache requests.
+class AppCacheURLLoaderFactory : public mojom::URLLoaderFactory {
+ public:
+  ~AppCacheURLLoaderFactory() override;
+
+  // Factory function to create an instance of the factory.
+  // The |appcache_service| parameter is used to query the underlying
+  // AppCacheStorage instance to check if we can service requests from the
+  // AppCache. We pass unhandled requests to the network service retrieved from
+  // the |factory_getter|.
+  static void CreateURLLoaderFactory(mojom::URLLoaderFactoryRequest request,
+                                     ChromeAppCacheService* appcache_service,
+                                     URLLoaderFactoryGetter* factory_getter);
+
+  // mojom::URLLoaderFactory implementation.
+  void CreateLoaderAndStart(
+      mojom::URLLoaderAssociatedRequest url_loader_request,
+      int32_t routing_id,
+      int32_t request_id,
+      uint32_t options,
+      const ResourceRequest& request,
+      mojom::URLLoaderClientPtr client) override;
+  void SyncLoad(int32_t routing_id,
+                int32_t request_id,
+                const ResourceRequest& request,
+                SyncLoadCallback callback) override;
+
+ private:
+  AppCacheURLLoaderFactory(ChromeAppCacheService* appcache_service,
+                           URLLoaderFactoryGetter* factory_getter);
+
+  // Used to query AppCacheStorage to see if a request can be served out of the
+  /// AppCache.
+  scoped_refptr<ChromeAppCacheService> appcache_service_;
+
+  // Used to retrieve the network service factory to pass unhandled requests to
+  // the network service.
+  scoped_refptr<URLLoaderFactoryGetter> factory_getter_;
+
+  mojo::StrongBindingSet<mojom::URLLoaderFactory> loader_factory_bindings_;
+
+  DISALLOW_COPY_AND_ASSIGN(AppCacheURLLoaderFactory);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_APPCACHE_APPCACHE_URL_LOADER_FACTORY_H_