[7u6] Request for approval for CR 7128738 - dragged dialog freezes system on dispose

[Oleg Pekhovskiy]

Hi!

Please review this backport to push for CR: 
http://bugs.sun.com/view_bug.do?bug_id=7128738

Webrev for 7u6: http://cr.openjdk.java.net/~bagiras/7u6/7128738.1
JDK8 changeset: 
http://hg.openjdk.java.net/jdk8/awt-gate/jdk/rev/255dd9eddc10
Review thread: 
http://mail.openjdk.java.net/pipermail/awt-dev/2012-March/002348.html
Reviewed by: art, anthony

The code changes for 7u6 are identical to the ones in JDK8.

Thanks,
Oleg