Draft: wlr_seat_keyboard: broadcast modifiers
...to all clients rather than just the one with keyboard focus on keyboard enter/create, modifer press/release and wlr_seat_set_keyboard().
This enable clients such as panels to display the current keyboard layout without introducing new wayland protocols or other IPC.
Context:
- The keymap is forwarded to all clients in wlr_seat_set_keyboard().
- When a keymap contains multiple layouts, the selection is made via modifiers, which previously were only sent to the client with keyboard focus.
Tested with: https://github.com/johanmalm/keyboard-layout