EllisLab/CodeIgniter — pull request #2694 by brenjt (2013-10-22 00:32:26+00:00)
Title: Removed extra from $name, since it does not follow the format of other f...

...orm_ helpers. Form helpers use $extra as a string. On the form_input for example, the $extra is a string but placing extra in the first parameter results in an attribute on the resulting element called 'extra', whereas the drop down it does not. $extra is now passed along as works just as all other form_ methods do.