These values weren't wrapped before, which caused group_index_is_active
to stop working after a few group switches.
Also, the current group-wrapping function didn't take into consideration
actions such as LockGroup=-1, which need to wrap around, etc.
xkb_layout_index_t is unsigned, but it was used to hold possibly
negative values (e.g. locked_group is 0 and gets a -1 action).
This group wrapping function should now act like the XkbAdjustGroup
function from xserver, and at least ./test/interactive doesn't bring up
any problems with group switching any more.
Signed-off-by: Ran Benita <ran234@gmail.com>
67b03cea0b