Form constructor for configuration import form.
config_admin_import_form_submit()
function config_admin_import_form($form, &$form_state) {
// Retrieve a list of differences between last known state and active store.
$source_storage = drupal_container()
->get('config.storage.staging');
$target_storage = drupal_container()
->get('config.storage');
config_admin_sync_form($form, $form_state, $source_storage, $target_storage);
$form['actions'] = array(
'#type' => 'actions',
);
$form['actions']['submit'] = array(
'#type' => 'submit',
'#value' => t('Import all'),
);
return $form;
}