The main window still has blur applied to it after nested modal popups are closed

Steps to reproduce:
1. Create a Flex application window
2. open first modal popup
3. open second modal popup (opened by first modal popup)
4. close second modal popup
5. close first modal popup
6. main window will still have blur applied to it

Actual Results:
The main window still has blur applied to it. It is not reset when all modal popups are closed.

Expected Results:
The main window should not have blur applied after all modal popups are closed.

Workaround (if any):
Open and close a modal popup. Blur is removed from main window.

Notes:
This worked correctly in 4.13 and earlier releases.
It is definitely broken in 4.14.0 and 4.14.0 Nightly build Feb 28.
I have not tried more recent builds.
No obvious open bugs for this problem.