/** List up all the global bindings. */
private void promoteGlobalBindings() {
// promote any global bindings in the schema
XSSchemaSet schemas = Ring.get(XSSchemaSet.class);
for( XSSchema s : schemas.getSchemas() ) {
BindInfo bi = getBindInfo(s);
// collect all global customizations
model.getCustomizations().addAll(bi.toCustomizationList());