LibGUI: Transfer focus when checking exclusive button programmatically

When calling set_checked(true) on an exclusive button, we will now
transfer focus to the newly checked button if one of its now-unchecked
siblings had focus before.

This makes windows that place initial focus somewhere in a group of
radio buttons look nicer when they show up, since focus will be on
whichever radio button was pre-checked, which may not be the first one
in the group.

0 files changed, 0 insertions, 0 deletions