TEMPLATE_STRING_IF_INVALID added to URL's when creating a new user in the admin panel

[crunchorn <crunchorn@…>]

When TEMPLATE_STRING_IF_INVALID is set in the Settings.py (for example: TEMPLATE_STRING_IF_INVALID = '---!_ERR_!---') you can't create a new user from admin panel beacause it is concatenated with links like ' Save and add another ', ' Save ', ' Save and continue editing ' and above the admin panels header.

Finnaly they look like:
​http://localhost:7777/admin/auth/user/add/---!_ERR_!---

After clicking on the links mentioned above i get following error:

ValueError at /admin/auth/user/add/---!_ERR_!---
invalid literal for int() with base 10: 'add/---!_ERR_!---'

Traceback is available on: ​http://dpaste.com/hold/90709/

Settings.py: ​http://dpaste.com/hold/90708/

[Karen Tracey]

Dup of #9051, #5532, #4279, and #3579 -- it's also documented that admin relies on this setting being empty.

[(none)]

Milestone post-1.0 deleted