Form submission handler for EntityTranslationController::entityFormAlter().
Takes care of entity translation deletion.
function entityFormDeleteTranslation($form, &$form_state) {
$form_controller = translation_entity_form_controller($form_state);
$entity = $form_controller
->getEntity($form_state);
$base_path = $this
->getBasePath($entity);
$form_langcode = $form_controller
->getFormLangcode($form_state);
$form_state['redirect'] = $base_path . '/translations/delete/' . $form_langcode;
}