[7u6] Request for approval for 7160293: [macosx] FileDialog appears on secondary display

[Dmitry Cherepanov]

This is a request to push the following fix:

Bug: http://bugs.sun.com/view_bug.do?bug_id=7160293

Webrev: http://cr.openjdk.java.net/~dcherepanov/7160293/7u6/webrev.0/

Technical review: 
http://mail.openjdk.java.net/pipermail/macosx-port-dev/2012-May/004265.html

Thanks,
Dmitry