[7u12] Request for approval: 7198073: (prefs) user prefs not saved [macosx]

[Kurchi Hazra]

This is a request for approval to backport the fix for 7198073 from 8 to 
7u12.

Bug: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7198073
Webrev: http://cr.openjdk.java.net/~khazra/7198073/7u12/webrev/

This change been reviewed by Alan Bateman [1] and the fix has been 
pushed into jdk8 [2].
The fix for 7u12 is identical.

Thanks,
Kurchi

[1]http://mail.openjdk.java.net/pipermail/core-libs-dev/2012-October/011767.html
[2]http://hg.openjdk.java.net/jdk8/tl/jdk/rev/3a6b76a468bd