[7u12] Review request for 7199708 FileChooser crashs when opening large folder

[Alexander Scherbatiy]

This is a direct backport of the fix from the JDK 8 to JDK 7u12
bug: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7199708
webrev: http://cr.openjdk.java.net/~alexsch/7199708/webrev.00

The Win32ShellFolder2 can dispose the pIShellFolder after passing it to 
the ColumnComparator.
The fix store the Win32ShellFolder2 reference to the ColumnComparator 
class to prevent the pIShellFolder disposing.

Thanks,
Alexandr.