Some reports are not showing the correct data if the workflow is changed.

Summary

Some reports (ie Velocity Report, Sprint Report) are not showing the correct data if the workflow is changed.

Steps to reproduce

1. Create a new Scrum project which will have 3 statuses (To Do, In Progress and Done)
2. Create some issues, add some Story Points and create a new Sprint
3. Add those issues in a Sprint and start it.
4. Drag the issues to the right most column to complete it.
5. Complete the Sprint
6. Check on Velocity/Sprint report and data are showing correctly
   • Velocity report: Completed SP has some values in it
   • Sprint Report: Completed issues are in Done status
7. Edit the workflow and remove Done status
8. Add a new status in it (ie Resolved)
9. Publish the workflow
10. Go to the board's column configuration
11. Drag Resolved status to the right most column
12. Drag Done status to Unmapped column to remove it.
13. Go back to the Report.

Actual Result

• Velocity Report: Completed SP is changed to 0
• Sprint Report: All the previously completed issues that were in Done status, are now changed to the previous status (ie. To Do or In Progress).

Expected Result

• Velocity Report: Completed SP is still showing the old data.
• Sprint Report: All completed issues are still with Done or Resolved status.