Refactoring DownloadManager::DownloadURL to add proper annotation.

components/download/internal/test/test_download_driver.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 COMPONENTS_DOWNLOAD_INTERNAL_TEST_TEST_DOWNLOAD_DRIVER_H_
 #define COMPONENTS_DOWNLOAD_INTERNAL_TEST_TEST_DOWNLOAD_DRIVER_H_
 
 #include <map>
 #include <memory>
 
 #include "base/macros.h"
 #include "components/download/internal/download_driver.h"
+#include "net/traffic_annotation/network_traffic_annotation.h"
 
 namespace download {
 namespace test {
 
 // Download driver that simulates content layer download logic.
 class TestDownloadDriver : public DownloadDriver {
  public:
   TestDownloadDriver();
   ~TestDownloadDriver() override;
 
   // Marks download driver as ready, used to test logic that depends on
   // data initialization.
   void MakeReady();
 
   // Simulates download events from content layer.
   void NotifyDownloadUpdate(const DriverEntry& entry);
   void NotifyDownloadFailed(const DriverEntry& entry, int reason);
   void NotifyDownloadSucceeded(const DriverEntry& entry,
                                const base::FilePath& path);
 
   // DownloadDriver implementation.
   void Initialize(DownloadDriver::Client* client) override;
   bool IsReady() const override;
-  void Start(const DownloadParams& params) override;
+  void Start(
+      const DownloadParams& params,
+      const net::NetworkTrafficAnnotationTag& traffic_annotation) override;
   void Cancel(const std::string& guid) override;
   void Pause(const std::string& guid) override;
   void Resume(const std::string& guid) override;
   base::Optional<DriverEntry> Find(const std::string& guid) override;
 
  private:
   bool is_ready_;
   DownloadDriver::Client* client_;
 
   // Map of guid --> DriverEntry.
   std::map<std::string, DriverEntry> entries_;
 
   DISALLOW_COPY_AND_ASSIGN(TestDownloadDriver);
 };
 
 }  // namespace test
 }  // namespace download
 
 #endif  // COMPONENTS_DOWNLOAD_CONTENT_TEST_TEST_DOWNLOAD_DRIVER_H_