Send out coordinates with pointer_focus event

We can't rely on motion events happening right away, pointer_focus could
change because of windows coming or going etc.
diff --git a/clients/window.c b/clients/window.c
index c01ca05..b2c4f03 100644
--- a/clients/window.c
+++ b/clients/window.c
@@ -400,7 +400,8 @@
 static void
 window_handle_pointer_focus(void *data,
 			    struct wl_input_device *input_device,
-			    uint32_t time, struct wl_surface *surface)
+			    uint32_t time, struct wl_surface *surface,
+			    int32_t x, int32_t y, int32_t sx, int32_t sy)
 {
 	struct input *input = data;