Enable use_once_callback for //content/common/*.mojom

content/browser/loader/url_loader_factory_impl.h

 // Copyright 2016 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_LOADER_URL_LOADER_FACTORY_IMPL_H_
 #define CONTENT_BROWSER_LOADER_URL_LOADER_FACTORY_IMPL_H_
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 13 matching lines @@
 
   void CreateLoaderAndStart(mojom::URLLoaderAssociatedRequest request,
                             int32_t routing_id,
                             int32_t request_id,
                             uint32_t options,
                             const ResourceRequest& url_request,
                             mojom::URLLoaderClientPtr client) override;
   void SyncLoad(int32_t routing_id,
                 int32_t request_id,
                 const ResourceRequest& request,
-                const SyncLoadCallback& callback) override;
+                SyncLoadCallback callback) override;
 
   static void CreateLoaderAndStart(ResourceRequesterInfo* requester_info,
                                    mojom::URLLoaderAssociatedRequest request,
                                    int32_t routing_id,
                                    int32_t request_id,
                                    const ResourceRequest& url_request,
                                    mojom::URLLoaderClientPtr client);
   static void SyncLoad(ResourceRequesterInfo* requester_info,
                        int32_t routing_id,
                        int32_t request_id,
                        const ResourceRequest& request,
-                       const SyncLoadCallback& callback);
+                       SyncLoadCallback callback);
 
   // Creates a URLLoaderFactoryImpl instance. The instance is held by the
   // StrongBinding in it, so this function doesn't return the instance.
   CONTENT_EXPORT static void Create(
       scoped_refptr<ResourceRequesterInfo> requester_info,
       mojom::URLLoaderFactoryRequest request,
       const scoped_refptr<base::SingleThreadTaskRunner>& io_thread_runner);
 
  private:
   explicit URLLoaderFactoryImpl(
       scoped_refptr<ResourceRequesterInfo> requester_info,
       const scoped_refptr<base::SingleThreadTaskRunner>& io_thread_runner);
 
   scoped_refptr<ResourceRequesterInfo> requester_info_;
 
   // Task runner for the IO thead.
   scoped_refptr<base::SingleThreadTaskRunner> io_thread_task_runner_;
 
   DISALLOW_COPY_AND_ASSIGN(URLLoaderFactoryImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_LOADER_URL_LOADER_FACTORY_IMPL_H_