Ubuntu linux 16.04, JDK9 b154.

> FAIL result should be /1:focused text field /2: /3:focused text field /4:. Was /1:focused first button /2:focused text field /3:focused second button /4:.
Pressing shift-tab 4 times:
> FAIL result should be /1:focused text field /2: /3:focused text field /4:. Was /1:focused second button /2:focused text field /3:focused first button /4:.