Use `__CLASS__` instead of `self`

Before it worked, because `WP_DEBUG` was off and the test magically
passed.

Props scribu, see #UT101.


git-svn-id: https://unit-tests.svn.wordpress.org/trunk@1198 4a5a2adb-35eb-4268-9a1b-fe04a4134342
Rename generators to formatters


git-svn-id: https://unit-tests.svn.wordpress.org/trunk@1199 4a5a2adb-35eb-4268-9a1b-fe04a4134342