Notify field.module that a bundle was renamed.
$entity_type: The entity type to which the bundle is bound.
$bundle_old: The previous name of the bundle.
$bundle_new: The new name of the bundle.
function field_attach_rename_bundle($entity_type, $bundle_old, $bundle_new) {
db_update('field_config_instance')
->fields(array(
'bundle' => $bundle_new,
))
->condition('entity_type', $entity_type)
->condition('bundle', $bundle_old)
->execute();
// Clear the cache.
field_cache_clear();
// Update bundle settings.
$settings = variable_get('field_bundle_settings_' . $entity_type . '__' . $bundle_old, array());
variable_set('field_bundle_settings_' . $entity_type . '__' . $bundle_new, $settings);
variable_del('field_bundle_settings_' . $entity_type . '__' . $bundle_old);
// Let other modules act on renaming the bundle.
module_invoke_all('field_attach_rename_bundle', $entity_type, $bundle_old, $bundle_new);
}