When use creates a default or new tab using a language switch in url (i.e. <web_site_url/fr) make sure we set real Web Site context rather than temporary one.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@41457 20353a03-c40f-0410-a6d1-a30d3c3de9de