Fix HTML literal for hidden form field

tailbone/forms/core.py

@@ -925,7 +925,8 @@ class Form(object):
         else: # hidden field
 
             # can just do normal thing for these
-            return field.serialize()
+            # TODO: again, why does serialize() not return literal?
+            return HTML.literal(field.serialize())
 
     def render_field_readonly(self, field_name, **kwargs):
         """