Bug#1174540. Some warnings were because the placeholder empty elements
returned the license_form_el_* functions were missing their "type". Others
were because code for some content was trying to process the license elements
even if licenses were disabled and thus the elements were missing.

Signed-off-by: Aaron Wells <aaronw@catalyst.net.nz>
Change-Id: I961fec3aa4fefb737b497638c59a0426db95d04b