Remove unused debug code from tests

 - Removed a var_export() call from a secure prepopulate test and repaired some of the secure prepopulate tests.
 - Removed var_export() calls from commerce_litle_test module.
 - Removed a commented out debug() call from an email wrappers test.
 - Removed a commented out debug() from a fundraiser_commerce test.

That constant doesn't exist. I got this solution from the webform test code.