shell: Expose set_transient in shell interface
diff --git a/src/compositor.h b/src/compositor.h
index 1d3e060..0ba51d7 100644
--- a/src/compositor.h
+++ b/src/compositor.h
@@ -63,6 +63,9 @@
 				     struct shell_surface **ret);
 	void (*set_toplevel)(struct shell_surface *shsurf);
 
+	void (*set_transient)(struct shell_surface *shsurf,
+			      struct shell_surface *pshsurf,
+			      int x, int y, uint32_t flags);
 	int (*move)(struct shell_surface *shsurf, struct weston_seat *ws);
 };