widl: Make structs containing user types bogus; fix square_test_us test failure.

dlls/rpcrt4/tests/server.c

@@ -698,7 +698,7 @@ pointer_tests(void)
 
   ok(test_list_length(list) == 3, "RPC test_list_length\n");
   ok(square_puint(p1) == 121, "RPC square_puint\n");
-  todo_wine ok(square_test_us(&tus) == 121, "RPC square_test_us\n");
+  ok(square_test_us(&tus) == 121, "RPC square_test_us\n");
 
   pa[0] = &a[0];
   pa[1] = &a[1];

tools/widl/parser.y

@@ -1740,6 +1740,9 @@ static int get_struct_type(var_list_t *fields)
   {
     type_t *t = field->type;
 
+    if (is_user_type(t))
+      return RPC_FC_BOGUS_STRUCT;
+
     if (is_ptr(t))
     {
         do