Create the BackgroundFetchBatchManager and initiate a download.

content/browser/background_fetch/fetch_request.cc

-// 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.
-
-#include "content/browser/background_fetch/fetch_request.h"
-
-#include <string>
-
-#include "base/guid.h"
-#include "content/public/browser/download_item.h"
-
-namespace content {
-
-FetchRequest::FetchRequest() = default;
-
-FetchRequest::FetchRequest(const url::Origin& origin,
-                           const GURL& url,
-                           int64_t service_worker_registration_id,
-                           const std::string& tag)
-    : guid_(base::GenerateGUID()),
-      origin_(origin),
-      url_(url),
-      service_worker_registration_id_(service_worker_registration_id),
-      tag_(tag) {}
-
-FetchRequest::FetchRequest(const FetchRequest& request)
-    : guid_(request.guid_),
-      origin_(request.origin_),
-      url_(request.url_),
-      service_worker_registration_id_(request.service_worker_registration_id()),
-      tag_(request.tag_) {}
-
-FetchRequest::~FetchRequest() = default;
-
-}  // namespace content