Private file system is not compatible with Ultimate Cron and Multi-languages

Hi,

This is the same bug as the 2559429, but it occurs when the drupal multi-languages is enabled.

To reproduce :

1. Install fresh Drupal 7 and configure default file download method as 'Private local files served by Drupal'. Private file system path: sites/default/files/private.
2. Tune your front web-server properly. For nginx it's:
   

   location ^~ /sites/default/files/private/ {
       internal;
   }

3. Configure some module that manages private files access rights. I use this one: https://www.drupal.org/project/private_files_download_permission. Configure it so that the root private files path (sites/default/files/private/) be accessible for e.g. admin.
4. Download and enable UC:
   drush dl ultimate_cron && drush en -y ultimate_cron
5. Enable Locale module
6. Add a new language (for example French) : admin/config/regional/language/add : Select 'French' and click "Add language"
7. Configure language detection method : admin/config/regional/language/configure : Enable URL method (Determine the language from the URL (Path prefix or domain)) and click "Save settings"
8. Configure part of the URL that determines language : admin/config/regional/language/configure/url : Choose "Path prefix" and click "Save configuration"
9. Go to your private directory and create a dummy file:
   cd <Drupal_Root>/sites/default/files/private/; dd if=/dev/zero of=test400.dat bs=1M count=400
10. Try to download (as an admin) with url : http://your-site/system/files/test400.dat => Download OK
11. Try to download (as an admin) with url : http://your-site/fr/system/files/test400.dat => Download KO with PHP error :
    PHP Fatal error: Allowed memory size of 268435456 bytes exhausted (tried to allocate 132136960 bytes) in /var/www/drupal/includes/file.inc on line 1994

When multi-languages is enabled file_create_url() method with private file return an URI with current language prefix.
For example: if current language is french, file_create_url('private://test400.dat'); return an URI like fr/system/files/test400.dat.

So when :

• a module uses file_create_url()
• private files are used
• multi-languages is enabled
• downloaded file size exceeds the memory limit

the issue occurs.

Aurélien