Wayland: Emulate frame event for old wl_seat versions

Multiwindow support simplified input handling by processing all data
only during a `wl_seat::frame` event, which got introduced in wl_seat
version 5. If the compositor reports an older version, we manually call
the frame event handler.

platform/linuxbsd/wayland/wayland_thread.cpp

@@ -1547,6 +1547,10 @@ void WaylandThread::_wl_pointer_on_enter(void *data, struct wl_pointer *wl_point
 	seat_state_update_cursor(ss);
 
 	DEBUG_LOG_WAYLAND_THREAD(vformat("Pointer entered window %d.", ws->id));
+
+	if (wl_pointer_get_version(wl_pointer) < WL_POINTER_FRAME_SINCE_VERSION) {
+		_wl_pointer_on_frame(data, wl_pointer);
+	}
 }
 
 void WaylandThread::_wl_pointer_on_leave(void *data, struct wl_pointer *wl_pointer, uint32_t serial, struct wl_surface *surface) {
@@ -1570,6 +1574,10 @@ void WaylandThread::_wl_pointer_on_leave(void *data, struct wl_pointer *wl_point
 	pd.pressed_button_mask.clear();
 
 	DEBUG_LOG_WAYLAND_THREAD(vformat("Pointer left window %d.", id));
+
+	if (wl_pointer_get_version(wl_pointer) < WL_POINTER_FRAME_SINCE_VERSION) {
+		_wl_pointer_on_frame(data, wl_pointer);
+	}
 }
 
 void WaylandThread::_wl_pointer_on_motion(void *data, struct wl_pointer *wl_pointer, uint32_t time, wl_fixed_t surface_x, wl_fixed_t surface_y) {
@@ -1582,6 +1590,10 @@ void WaylandThread::_wl_pointer_on_motion(void *data, struct wl_pointer *wl_poin
 	pd.position.y = wl_fixed_to_double(surface_y);
 
 	pd.motion_time = time;
+
+	if (wl_pointer_get_version(wl_pointer) < WL_POINTER_FRAME_SINCE_VERSION) {
+		_wl_pointer_on_frame(data, wl_pointer);
+	}
 }
 
 void WaylandThread::_wl_pointer_on_button(void *data, struct wl_pointer *wl_pointer, uint32_t serial, uint32_t time, uint32_t button, uint32_t state) {
@@ -1629,6 +1641,10 @@ void WaylandThread::_wl_pointer_on_button(void *data, struct wl_pointer *wl_poin
 
 	pd.button_time = time;
 	pd.button_serial = serial;
+
+	if (wl_pointer_get_version(wl_pointer) < WL_POINTER_FRAME_SINCE_VERSION) {
+		_wl_pointer_on_frame(data, wl_pointer);
+	}
 }
 
 void WaylandThread::_wl_pointer_on_axis(void *data, struct wl_pointer *wl_pointer, uint32_t time, uint32_t axis, wl_fixed_t value) {
@@ -1648,6 +1664,10 @@ void WaylandThread::_wl_pointer_on_axis(void *data, struct wl_pointer *wl_pointe
 	}
 
 	pd.button_time = time;
+
+	if (wl_pointer_get_version(wl_pointer) < WL_POINTER_FRAME_SINCE_VERSION) {
+		_wl_pointer_on_frame(data, wl_pointer);
+	}
 }
 
 void WaylandThread::_wl_pointer_on_frame(void *data, struct wl_pointer *wl_pointer) {