Provider extension to integrate external assessment sources with the gradebook.
This is an extension of ExternalAssignmentProvider, only here for backward
compatibility of the 2.9 API. The reason it is added is to support tools
that participate in the gradebook but have not implemented the provider.
Before this was implemented, external items for tools without a provider
could never be visible in the student view of the gradebook.
This interface should be merged into ExternalAssignmentProvider for the next
See also: https://jira.sakaiproject.org/browse/SAK-23733
See also: https://jira.sakaiproject.org/browse/SAK-19668