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

content/browser/download/save_package.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.
 
 #ifndef CONTENT_BROWSER_DOWNLOAD_SAVE_PACKAGE_H_
 #define CONTENT_BROWSER_DOWNLOAD_SAVE_PACKAGE_H_
 #pragma once
 
 #include <queue>
 #include <string>
@@ skipping 111 matching lines @@
 
   bool canceled() const { return user_canceled_ || disk_error_occurred_; }
   bool finished() const { return finished_; }
   SavePackageType save_type() const { return save_type_; }
   int tab_id() const { return tab_id_; }
   int id() const { return unique_id_; }
   TabContents* tab_contents() const {
     return TabContentsObserver::tab_contents();
   }
 
+  // Determines the saved file name based on the information of the
+  // current page, and then starts to download the page. This method
+  // runs in the background and may finish asynchronously after this
+  // method returns.
   void GetSaveInfo();
 
   // Statics -------------------------------------------------------------------
 
   // Check whether we can do the saving page operation for the specified URL.
   static bool IsSavableURL(const GURL& url);
 
   // Check whether we can do the saving page operation for the contents which
   // have the specified MIME type.
   static bool IsSavableContents(const std::string& contents_mime_type);
@@ skipping 177 matching lines @@
   friend class SavePackageTest;
   FRIEND_TEST_ALL_PREFIXES(SavePackageTest, TestSuggestedSaveNames);
   FRIEND_TEST_ALL_PREFIXES(SavePackageTest, TestLongSafePureFilename);
 
   ScopedRunnableMethodFactory<SavePackage> method_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SavePackage);
 };
 
 #endif  // CONTENT_BROWSER_DOWNLOAD_SAVE_PACKAGE_H_