NimbusL&F :Regression in Focus traversal in JFileChooser in pit build.

Focus is not going to few buttons in the file chooser when foward traversal & backward traversal is done using focus traversal keys .

Step to Reproduce:
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1) Run SwingSet2.
2) Select JFileChooser demo.
3) Click on 'Show Plain JFileChooser'.
4) Select any drive which is having all permission. i,e selec 'c' drive & select any folder.
5) click on 'look In' combobox. so that it can get the focus.
6) press tab so the 'Up one level' button get the focus.
7) press tab , so that 'Desktop' button get the focus.
8) press tab, so that 'Create new folder' button get the focus. Observe that focus goes to 'List' button ,if you see the same then bug is reproduce. Actually 'Create new folder' button should get the focus.
9) Press 'Shift + Tab' ( backward traversal) & observe that focus should travel to all button , but focus dn't come to 'List' & 'Detail' buttons. If you see the same then the bug is reproduced.

This is observed in windows platform only. I checked in linux & solaris sparc its working fine. I tested on windows vista home premium. It works fine in 6u5-b03 promoted build. Hence its a regression introduced in pit build.