[7u6] Please review my fix for 7173487: [macosx] Problems with popup menus, tooltips and dialog boxes in dual monitor setup

[Alexander Zuev]

Hello,

   please review my fix for CR 7173487: [macosx] Problems with popup 
menus, tooltips and dialog boxes in dual monitor setup

   CR description can be found here: 
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7173487

   Webrev with the proposed change can be seen here: 
http://cr.openjdk.java.net/~kizune/7173487/webrev.00

   This is a backport of the fix implemented for jdk8.

With best regards,
Alex