<Swing Dev> [9] Review Request: 8043610 Sorting columns in JFileChooser fails with AppContext NPE

[Petr Pchelko]

Hello, AWT Team.

Please review the fix for the issue:
https://bugs.openjdk.java.net/browse/JDK-8043610
The fix is available at:
http://cr.openjdk.java.net/~pchelko/9/8043610/webrev/

The problem is that JComponent has 3 methods which are known to be safe to call from any thread - invalidate, revalidate and repaint. 
So these are OK to call from ThreadPool's threads. But now ThreadPool threads do not have an AppContext, so the methods should be
updated to work correctly event on the thread that does not have AppContext.

With best regards. Petr.