Issue #2153293 by ParisLiakos: Remove unused parameter in AggregatorController::opmlPage.

core/modules/aggregator/aggregator.routing.yml

@@ -96,10 +96,9 @@ aggregator.sources:
     _permission: 'access news feeds'
 
 aggregator.opml_page:
-  path: '/aggregator/opml/{cid}'
+  path: '/aggregator/opml'
   defaults:
     _title: 'OPML feed'
     _controller: '\Drupal\aggregator\Controller\AggregatorController::opmlPage'
-    cid: null
   requirements:
     _permission: 'access news feeds'

core/modules/aggregator/lib/Drupal/aggregator/Controller/AggregatorController.php

@@ -249,7 +249,7 @@ public function sources() {
    * @return \Symfony\Component\HttpFoundation\Response
    *   The response containing the OPML.
    */
-  public function opmlPage($cid = NULL) {
+  public function opmlPage() {
     $result = $this->database->query('SELECT * FROM {aggregator_feed} ORDER BY title');
 
     $feeds = $result->fetchAll();