JfileChooser OK and Cancel button Icons are different than Native FileDialog icons
Steps to Reproduce:
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1) Run SwingSet2 on Mercury. Change the L&F to GTK.
2) Go to FileChooser Demo.
3) Open 'Show Plain JFileChooser' and notice the Ok and Cancel Button icons
4) Now open Gedit .
5) Click Open and notice the Ok and Cancel button Icons.