Steps to reproduce:(with/without VO on)
1. Run SwingSet2.jar from demos.
2. Tab until the Button Demo icon has focus. Press 'space' to choose.
3. Tab until the "Button Demo" tab has focus. Press 'space'. Press 'tab'.
4. Use the arrow keys to navigate to "Radio Buttons" tab.
5. Tab several times to Image Radio Buttons,
6. The image radio buttons should have focus.
7. Use the arrow keys to navigate to "Check Boxes" tab.
8. The Check Boxes should have focus.

Actual results:
At step6 and step 8,the focus is invisible when tab to "Image Radio Buttons" and "Image CheckBoxes",but when pressing spacebar,the buttons/checkboxes can be selected.Please refer to RadioButtons.png and CheckBoxes.png