Update to Drupal 8.0.5. For more information, see https://www.drupal.org/node/2679347

core/modules/link/src/LinkItemInterface.php

@@ -41,7 +41,7 @@ interface LinkItemInterface extends FieldItemInterface {
    * Gets the URL object.
    *
    * @return \Drupal\Core\Url
-   *   Returns an Url object.
+   *   Returns a Url object.
    */
   public function getUrl();
 

core/modules/link/src/Plugin/Field/FieldFormatter/LinkFormatter.php

@@ -240,7 +240,7 @@ class LinkFormatter extends FormatterBase implements ContainerFactoryPluginInter
    *   The link field item being rendered.
    *
    * @return \Drupal\Core\Url
-   *   An Url object.
+   *   A Url object.
    */
   protected function buildUrl(LinkItemInterface $item) {
     $url = $item->getUrl() ?: Url::fromRoute('<none>');