Actions: Break latch on modifier/group changes

Right now, only a few actions result in breaking a key latch. Add
modifier/group actions to this, as presumably the effect of the latch
should not last beyond already shifting the modifier/group state.

This was discovered with a real-world use in an input device for the
physically impaired, where shift latches, but pressing shift twice goes
to caps lock (note shift vs. caps lock, so not pure latch-to-lock). This
is possible to implement with current keymap files, but locking caps
lock would not break the shift latch. Hence, the following key sequence:

[Shift] [a -> a] [Shift] [Shift] [b -> b] [c -> C]

would occur, as the modifier state when pressing b was lock locked and
shift latched. With this patch, the sequence is correct:

[Shift] [a -> a] [Shift] [Shift -> Lock] [b -> B] [c -> C]

Signed-off-by: Daniel Stone <[email protected]>

src/state.c

@@ -430,6 +430,12 @@ xkb_action_breaks_latch(const union xkb_action *action)
     case ACTION_TYPE_CTRL_LOCK:
     case ACTION_TYPE_SWITCH_VT:
     case ACTION_TYPE_TERMINATE:
+    case ACTION_TYPE_MOD_SET:
+    case ACTION_TYPE_MOD_LATCH:
+    case ACTION_TYPE_MOD_LOCK:
+    case ACTION_TYPE_GROUP_SET:
+    case ACTION_TYPE_GROUP_LATCH:
+    case ACTION_TYPE_GROUP_LOCK:
         return true;
     default:
         return false;