wayland: Update cursor surface scale when output scale changes

Also update the cursor surfaces of every seat when an output changes
scale. This could for example happen when a monitor scale is changed via
Settings.

gdk/wayland/gdkdevice-wayland.c

@@ -4516,6 +4516,12 @@ pointer_surface_update_scale (GdkDevice *device)
   gdk_wayland_device_update_surface_cursor (device);
 }
 
+void
+gdk_wayland_seat_update_cursor_scale (GdkWaylandSeat *seat)
+{
+  pointer_surface_update_scale (seat->master_pointer);
+}
+
 static void
 pointer_surface_enter (void              *data,
                        struct wl_surface *wl_surface,

gdk/wayland/gdkdisplay-wayland.c

@@ -38,6 +38,7 @@
 #include "gdkdisplay.h"
 #include "gdkdisplay-wayland.h"
 #include "gdkmonitor-wayland.h"
+#include "gdkseat-wayland.h"
 #include "gdkinternals.h"
 #include "gdkdeviceprivate.h"
 #include "gdkkeysprivate.h"
@@ -1871,9 +1872,20 @@ transform_to_string (int transform)
 static void
 update_scale (GdkDisplay *display)
 {
+  GList *seats;
+  GList *l;
+
   g_list_foreach (gdk_wayland_display_get_toplevel_surfaces (display),
                   (GFunc)gdk_wayland_surface_update_scale,
                   NULL);
+  seats = gdk_display_list_seats (display);
+  for (l = seats; l; l = l->next)
+    {
+      GdkSeat *seat = l->data;
+
+      gdk_wayland_seat_update_cursor_scale (GDK_WAYLAND_SEAT (seat));
+    }
+  g_list_free (seats);
 }
 
 static void

gdk/wayland/gdkseat-wayland.h

@@ -41,4 +41,6 @@ struct _GdkWaylandSeatClass
 
 GType gdk_wayland_seat_get_type (void) G_GNUC_CONST;
 
+void gdk_wayland_seat_update_cursor_scale (GdkWaylandSeat *seat);
+
 #endif /* __GDK_WAYLAND_SEAT_H__ */