output-management-v1: add assertion as a safety net
Makes it easier to figure out when the compositor submits an invalid
output state.
References:
@@ -686,6 +686,9 @@ static void head_send_state(struct wlr_output_head_v1 *head,
}
if (state & HEAD_STATE_MODE) {
+ assert(head->state.mode != NULL ||
+ wl_list_empty(&head->state.output->modes));
+
bool found = false;
struct wl_resource *mode_resource;
wl_resource_for_each(mode_resource, &head->mode_resources) {
