Fixed #12864 -- Corrected handling of new user creation when a multi-database...

Fixed #12864 -- Corrected handling of new user creation when a multi-database router is in place. Thanks to haris@dubizzle.com for the report.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@12488 bcc190cf-cafb-0310-a4f2-bffc1f526a37