Velocity and Sprint report broken when the end status is changed in the worklfow

Summary

When the end status of a workflow is change for a project and the board, the historical sprint and velocity reports will be broken.

Steps to Reproduce

1. Create a project and board with the following flow (To Do, In Progress, Done).
2. Perform some sprints to generate some reports.
3. Change the Done status to Closed in the workflow.
4. Update the board to use the new Closed status.
5. Remove the old Done status from the board column configuration (move to unmapped). The status will then dissappear from the column configurations.

Check the Velocity and Sprint reports.

Expected Results

The reports should still work for historical sprints.

Actual Results

Sprint report indicates that the issues were removed.

Velocity report shows no completed issues.

Notes

Burndown report still indicates the correct completed times.

Workaround

Add the old status back to the Workflow configuration (without any transition) and map that status to the right most column configuration of the board.