diff --git a/core/modules/aggregator/aggregator.pages.inc b/core/modules/aggregator/aggregator.pages.inc
index 98dc665..0fa2bd8 100644
--- a/core/modules/aggregator/aggregator.pages.inc
+++ b/core/modules/aggregator/aggregator.pages.inc
@@ -157,7 +157,7 @@ function _aggregator_page_list($items, $op, $feed_source = '') {
     $build['feed_source'] = is_array($feed_source) ? $feed_source : array('#markup' => $feed_source);
     if ($items) {
       $build['items'] = entity_view_multiple($items, 'default');
-      $build['pager']['#markup'] = theme('pager');
+      $build['pager'] = array('#theme' => 'pager');
     }
   }
 
diff --git a/core/modules/aggregator/lib/Drupal/aggregator/Plugin/views/row/Rss.php b/core/modules/aggregator/lib/Drupal/aggregator/Plugin/views/row/Rss.php
index 7239213..98709ea 100644
--- a/core/modules/aggregator/lib/Drupal/aggregator/Plugin/views/row/Rss.php
+++ b/core/modules/aggregator/lib/Drupal/aggregator/Plugin/views/row/Rss.php
@@ -99,11 +99,13 @@ public function render($row) {
       ),
     );
 
-    return theme($this->themeFunctions(), array(
-      'view' => $this->view,
-      'options' => $this->options,
-      'row' => $item,
-    ));
+    $build = array(
+      '#theme' => $this->themeFunctions(),
+      '#view' => $this->view,
+      '#options' => $this->options,
+      '#row' => $item,
+    );
+    return drupal_render($build);
   }
 
 }