[1.2.X] Fixed some bugs with formtools tests.

Without these checks, it is possible for the tests to pass by virtue of
asserts never being reached for some reason (very possible in this case, due
to handling of security hashes).

Backport of [15198] from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.2.X@15200 bcc190cf-cafb-0310-a4f2-bffc1f526a37