PI Estimate on Epic Forecast tab behavior is not consistent

Issue Summary

The PI value after entering it on the forecast tab results in different data depending on if you save or just close the Epic window.  If you enter the PI estimate on an Epic's forecast tab and then close out of the Epic (do not click save or save and close) then the value showed in various places (forecast report, backlog, export) matches the value entered. 

However, if you enter the same value and click "Save" before closing the epic, then the value PI estimate value will be showed as a value rounded to the nearest T-shirt size.  This is incorrect, and inconsistent with the first scenario.

Steps to Reproduce

1. Go to an Epic and click on the forecast tab
2. Enter in a value in the PI Estimate box
3. Click save and close the Epic
4. Go to the Forecast report and look at the PI estimate value for this Epic

Expected Results

The value entered would be appearing

Actual Results

Instead of the value entered, the estimate has been rounded to the nearest t-shirt size

Workaround

The workaround is to not click "Save" after making changes to the PI Estimate, since the values entered this way are saving as expected.