compositor: Only set surface geometry through weston_surface_configure()

There are too many things to keep track of now, so let's require going
through this.
diff --git a/src/compositor.h b/src/compositor.h
index a7b2964..4bc4ba2 100644
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -369,8 +369,7 @@
 weston_compositor_top(struct weston_compositor *compositor);
 
 struct weston_surface *
-weston_surface_create(struct weston_compositor *compositor,
-		      int32_t x, int32_t y, int32_t width, int32_t height);
+weston_surface_create(struct weston_compositor *compositor);
 
 void
 weston_surface_configure(struct weston_surface *surface,