[9] Review request for 8078606: Deadlock in awt clipboard

[Anton Nashatyrev]

Hello,
    could you please review the following fix:
fix: http://cr.openjdk.java.net/~anashaty/8078606/webrev.00/ 
<http://cr.openjdk.java.net/%7Eanashaty/8078606/webrev.00/>
bug: https://bugs.openjdk.java.net/browse/JDK-8078606

    Problem: XClipboard sometimes deadlocked

    Reason: XClipboard.registerClipboardViewerChecked acquires 
XCliboard lock first, then tries to acquire AWTLock (within the 
XWindow.getXAWTRootWindow() call)

    Fix: reverse the order of acquiring locks. Additionally eliminate 
AWTLock when accessing XRootWindow singleton.

Thanks!
Anton.