<Swing Dev> RFR: 8233584: [Win LAF] When navigating the contents of the file list changes in Win LAF

[Bhawesh Choudhary]

Hi,

Please review this fix,
JBS:         https://bugs.openjdk.java.net/browse/JDK-8233584
Webrev: http://cr.openjdk.java.net/~psadhukhan/8233584/webrev/

Issue:
In Windows LookAndFeel, When navigating Combobox's list of JFileChooser 
via keys, the contents of JFileChooser changes.

Fix:
Set flag "JComboBox.isTableCellEditor" to True which prohibits JCombobox 
from sending selection change event when JCombobox's list selection 
change happens via keys.


Verification:
Tested the fix with JFileChooser with WindowsLookAndFeelEnabled as well 
as BasicLookAndFeel with keys navigation. also added a test case to 
verify the same.

Did not find any misbehavior with the fix.

Regards
Bhawesh