<Swing Dev> [9] Review Request for 8078269: JTabbedPane UI Property TabbedPane.tabAreaBackground no longer works

[Semyon Sadetsky]

Hello,

Please review fix for JDK9:

bug: https://bugs.openjdk.java.net/browse/JDK-8078269
webrev: http://cr.openjdk.java.net/~ssadetsky/8078269/webrev.00/

This is regression of the 8007563 which was incorrect fix of the 4690946 
regression.
Actually the 4690946 was a test bug because tab area's background can be 
controlled separately using "TabbedPane.tabAreaBackground" property.
Presence of "TabbedPane.tabAreaBackground" depends on L&F. Test of the 
4690946 is fixed to take this into account.

Also inappropriate design chosen for the 8007563 reg test code affected 
test results stability. It also has been fixed.

--Semyon