Use the user's preferred downloads directory for creating the initial download file.

content/public/browser/download_manager_delegate.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 CONTENT_PUBLIC_BROWSER_DOWNLOAD_MANAGER_DELEGATE_H_
 #define CONTENT_PUBLIC_BROWSER_DOWNLOAD_MANAGER_DELEGATE_H_
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/file_path.h"
 #include "base/logging.h"
 #include "base/time.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/download_danger_type.h"
 #include "content/public/browser/download_item.h"
 #include "content/public/browser/save_page_type.h"
 
 namespace content {
 
+class BrowserContext;
 class DownloadId;
 class WebContents;
 
 // Called by SavePackage when it creates a DownloadItem.
 typedef base::Callback<void(DownloadItem*)>
     SavePackageDownloadCreatedCallback;
 
 // Will be called asynchronously with the results of the ChooseSavePath
 // operation.  If the delegate wants notification of the download item created
 // in response to this operation, the SavePackageDownloadCreatedCallback will be
@@ skipping 91 matching lines @@
   // Notifies the delegate that it should remove the download item from its
   // persistent store.
   virtual void RemoveItemFromPersistentStore(DownloadItem* item) {}
 
   // Notifies the delegate to remove downloads from the given time range.
   virtual void RemoveItemsFromPersistentStoreBetween(
       base::Time remove_begin,
       base::Time remove_end) {}
 
   // Retrieve the directories to save html pages and downloads to.
-  virtual void GetSaveDir(WebContents* web_contents,
+  virtual void GetSaveDir(BrowserContext* browser_context,
                           FilePath* website_save_dir,
                           FilePath* download_save_dir,
                           bool* skip_dir_check) {}
 
   // Asks the user for the path to save a page. The delegate calls the callback
   // to give the answer.
   virtual void ChooseSavePath(WebContents* web_contents,
                               const FilePath& suggested_path,
                               const FilePath::StringType& default_extension,
                               bool can_save_as_complete,
                               const SavePackagePathPickedCallback& callback) {
   }
 
  protected:
   virtual ~DownloadManagerDelegate();
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_DOWNLOAD_MANAGER_DELEGATE_H_