Focus Rectangle not appearing on the JButton with setContentAreaFilled(false) on GTK L&F.
Steps to Reproduce
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1)Open Swingset2 demo,tab to Button Demo, switch to GTK L&F.
2)Uncheck the ContentFilled check box,Check the Paint Focus check box
3)Click on any of the buttons, tab to shift focus to next button.
Expected behavior
Focus Rectangle appears around the button currently in focus.
Observer behavior
Focus Rectangle does not appears around the button currently in focus.
This is reproducible the first time in the pit build for b74 and in all promoted builds thereafter.