<AWT Dev> [8] Review request for 8002191 AWT-Shutdown thread does not start with the AppletSecurity on Linux

[Alexander Scherbatiy]

bug: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=8002191
webrev: http://cr.openjdk.java.net/~alexsch/8002191/webrev.00

The AWT-Shutdown thread starts from the main thread on Linux and so it 
does not have modifyThreadGroup permissions.
The fix runs the AWT-Shutdown thread from the doPrivileged block.

The 'thread.setDaemon(false);' line is not formatted because hg diff 
(and so webrev) does not treat new spaces as a change.

Thanks,
Alexandr.