Make non-clickable item not focusable

Currently, even though the button is not clickable, it is still
focusable. This causes that if we want to click the button of the next
step, we should press DOWN key and move the focus.
Changed that the non-clickable item doesn't have focus.

Change-Id: I2a7ae5042205c1713ec9656e67c8c9ebbc392545
1 file changed