Local files won't import in install profile

Using an install profile that imports local translation files doesn't work with drush si.

The same install profile does import the translation files when you use the web interface.

  module_load_include('fetch.inc', 'l10n_update');
  $options = _l10n_update_default_update_options();
  $batch = l10n_update_batch_update_build(array(), array(), $options);

It think it has something to do with the project type, which is empty in l10n_update_batch_fetch_import

if ($source->type == L10N_UPDATE_REMOTE || $source->type == L10N_UPDATE_LOCAL) { ... }

After the installation is done, the translation files aren't imported. Running the drush commands to refresh and update the translations they get imported.