Use new API to download blobs from Google Drive.

components/drive/service/drive_api_service.h

 // Copyright (c) 2012 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_DRIVE_SERVICE_DRIVE_API_SERVICE_H_
 #define COMPONENTS_DRIVE_SERVICE_DRIVE_API_SERVICE_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 76 matching lines @@
 // This class provides Drive request calls using Drive V2 API.
 // Details of API call are abstracted in each request class and this class
 // works as a thin wrapper for the API.
 class DriveAPIService : public DriveServiceInterface,
                         public google_apis::AuthServiceObserver {
  public:
   // |oauth2_token_service| is used for obtaining OAuth2 access tokens.
   // |url_request_context_getter| is used to initialize URLFetcher.
   // |blocking_task_runner| is used to run blocking tasks (like parsing JSON).
   // |base_url| is used to generate URLs for communication with the drive API.
-  // |base_download_url| is used to generate URLs for downloading file from the
-  // drive API.
   // |base_thumbnail_url| is used to generate URLs for downloading thumbnail
   // from image server.
   // |custom_user_agent| will be used for the User-Agent header in HTTP
   // requests issues through the service if the value is not empty.
   DriveAPIService(
       OAuth2TokenService* oauth2_token_service,
       net::URLRequestContextGetter* url_request_context_getter,
       base::SequencedTaskRunner* blocking_task_runner,
       const GURL& base_url,
-      const GURL& base_download_url,
       const GURL& base_thumbnail_url,
       const std::string& custom_user_agent);
   ~DriveAPIService() override;
 
   // DriveServiceInterface Overrides
   void Initialize(const std::string& account_id) override;
   void AddObserver(DriveServiceObserver* observer) override;
   void RemoveObserver(DriveServiceObserver* observer) override;
   bool CanSendRequest() const override;
   bool HasAccessToken() const override;
@@ skipping 149 matching lines @@
   base::ObserverList<DriveServiceObserver> observers_;
   google_apis::DriveApiUrlGenerator url_generator_;
   const std::string custom_user_agent_;
 
   DISALLOW_COPY_AND_ASSIGN(DriveAPIService);
 };
 
 }  // namespace drive
 
 #endif  // COMPONENTS_DRIVE_SERVICE_DRIVE_API_SERVICE_H_