pub fn fluent_bundle(
    sysroot_candidates: &[&Path],
    requested_locale: Option<LanguageIdentifier>,
    additional_ftl_path: Option<&Path>,
    with_directionality_markers: bool,
) -> Result<Option<Arc<IntoDynSyncSend<FluentBundle<FluentResource, IntlLangMemoizer>>>>, TranslationBundleError>Expand description
Returns Fluent bundle with the user’s locale resources from
$sysroot/share/locale/$requested_locale/*.ftl.
If -Z additional-ftl-path was provided, load that resource and add it  to the bundle
(overriding any conflicting messages).