Fix typescript types in DOMLocalization (#643)

Author: julienw

fluent-dom/src/dom_localization.js

@@ -120,7 +120,7 @@ export default class DOMLocalization extends Localization {
    * Additionally, if this `DOMLocalization` has an observer, start observing
    * `newRoot` in order to translate mutations in it.
    *
-   * @param {Element}      newRoot - Root to observe.
+   * @param {Element | DocumentFragment}      newRoot - Root to observe.
    */
   connectRoot(newRoot) {
     for (const root of this.roots) {
@@ -158,7 +158,7 @@ export default class DOMLocalization extends Localization {
    * Returns `true` if the root was the last one managed by this
    * `DOMLocalization`.
    *
-   * @param   {Element} root - Root to disconnect.
+   * @param   {Element | DocumentFragment} root - Root to disconnect.
    * @returns {boolean}
    */
   disconnectRoot(root) {
@@ -269,7 +269,7 @@ export default class DOMLocalization extends Localization {
    *
    * Returns a `Promise` that gets resolved once the translation is complete.
    *
-   * @param   {DOMFragment} frag - Element or DocumentFragment to be translated
+   * @param   {Element | DocumentFragment} frag - Element or DocumentFragment to be translated
    * @returns {Promise}
    */
   translateFragment(frag) {
@@ -321,7 +321,7 @@ export default class DOMLocalization extends Localization {
   /**
    * Collects all translatable child elements of the element.
    *
-   * @param {Element} element
+   * @param {Element | DocumentFragment} element
    * @returns {Array<Element>}
    * @private
    */