A user will get the message that a concept can't be deleted because it has resources even though the concept has no resources. The following lead to this issue:

-The concept has resources
-User deletes all resources from the concept
-User closes portion of tree that has the concept shown, hiding the concept from the UI before deletes finish
-All deletes finish
-User reopens tree to show concept
-User attempts to delete concept

Possible solutions:
1) Do a sidora.util.refreshConceptChildrenNumber before attempting delete
or
2) update the delete functionality to use the underlying tree javascript data structure instead of using the jQuery UI to alter the resourcechildren attribute