Form submission handler for language_content_settings_form().
function language_content_settings_form_submit(array $form, array &$form_state) {
$entity_types = $form_state['values']['entity_types'];
$settings =& $form_state['values']['settings'];
foreach ($settings as $entity_type => $entity_settings) {
foreach ($entity_settings as $bundle => $bundle_settings) {
language_save_default_configuration($entity_type, $bundle, $bundle_settings['settings']['language']);
}
}
drupal_set_message(t('Settings successfully updated.'));
}