When the download folder does not exist, change the download folder to a user's "Downloads"

content/browser/renderer_host/resource_dispatcher_host.h

 // Copyright (c) 2011 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.
 
 // This is the browser side of the resource dispatcher, it receives requests
 // from the child process (i.e. [Renderer, Plugin, Worker]ProcessHost), and
 // dispatches them to URLRequests. It then forwards the messages from the
 // URLRequests back to the correct process for handling.
 //
 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
@@ skipping 73 matching lines @@
                      int process_unique_id,
                      int route_id,
                      const content::ResourceContext& context);
 
   // Initiates a save file from the browser process (as opposed to a resource
   // request from the renderer or another child process).
   void BeginSaveFile(const GURL& url,
                      const GURL& referrer,
                      int process_unique_id,
                      int route_id,
+                     const FilePath& default_download_dir,
                      const content::ResourceContext& context);
 
   // Cancels the given request if it still exists. We ignore cancels from the
   // renderer in the event of a download.
   void CancelRequest(int process_unique_id,
                      int request_id,
                      bool from_renderer);
 
   // Follows a deferred redirect for the given request.
   // new_first_party_for_cookies, if non-empty, is the new cookie policy URL
@@ skipping 389 matching lines @@
 
   ResourceDispatcherHostDelegate* delegate_;
 
   static bool is_prefetch_enabled_;
   bool allow_cross_origin_auth_prompt_;
 
   DISALLOW_COPY_AND_ASSIGN(ResourceDispatcherHost);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RESOURCE_DISPATCHER_HOST_H_