[7u6] Review request for 7144542: [macosx] Crash in liblwawt.dylib setBusy() when exiting an FX app run with j2d pipeline

[Anthony Petrov]

Hello,

Please review a fix for http://bugs.sun.com/view_bug.do?bug_id=7144542 at:

http://cr.openjdk.java.net/~anthony/7u6-6-crashInSetBusy-7144542.0/

Note: in JDK 8 we already load the headless version of the AWT library, 
and this prevents the crash. Now I'm applying the same logic to JDK 7u6.

--
best regards,
Anthony