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

chrome/browser/download/download_util.h

Index: chrome/browser/download/download_util.h
diff --git a/chrome/browser/download/download_util.h b/chrome/browser/download/download_util.h
index 50b930b49160762a9e10bbf6250499c1493abba2..de9f6db720044cc9a2638154c92281ffac557ec3 100644
--- a/chrome/browser/download/download_util.h
+++ b/chrome/browser/download/download_util.h
@@ -50,12 +50,20 @@ namespace download_util {
 
 // Download temporary file creation --------------------------------------------
 
-// Return the default download directory.
-const FilePath& GetDefaultDownloadDirectory();
-
-// Create a temporary file for a download in the user's default download
-// directory and return true if was successful in creating the file.
-bool CreateTemporaryFileForDownload(FilePath* path);
+// Chooses a writable directory from |website_save_dir|, |download_save_dir|
+// and |default_download_dir| in this order of priority.
+// If none of them is writable, creates |download_save_dir| and
+// chooses |download_save_dir|. The choosed directory is stored to |save_dir|.
+// Returns true if neither |website_save_dir| nor |download_save_dir|
+// is writable, which indicates the select file dialog should be displayed.
+bool ChooseSavableDirectory(const FilePath& website_save_dir,
+                            const FilePath& download_save_dir,
+                            const FilePath& default_download_dir,
+                            FilePath* save_dir);
+
+// Returns the user's default "Downloads" folder provided by PathService.
+// This method returns the folder provided by PathService.
+FilePath GetDefaultDownloadDirectoryFromPathService();
 
 // Return true if the |download_path| is dangerous path.
 bool DownloadPathIsDangerous(const FilePath& download_path);