Merge "make xml abstracts, stubs and page log dumps work again"

diff --combined maintenance/includes/BackupDumper.php
index 425bf36,f4d4d50..0b450a6
--- 1/maintenance/includes/BackupDumper.php
--- 2/maintenance/includes/BackupDumper.php
+++ b/maintenance/includes/BackupDumper.php
@@@ -26,6 -26,7 +26,7 @@@
   */
  
  require_once __DIR__ . '/../Maintenance.php';
+ require_once __DIR__ . '/../../includes/export/WikiExporter.php';
  
  use MediaWiki\MediaWikiServices;
  use Wikimedia\Rdbms\LoadBalancer;
@@@ -163,7 -164,8 +164,7 @@@ abstract class BackupDumper extends Mai
  
                $options = $this->orderedOptions;
                foreach ( $options as $arg ) {
 -                      $opt = $arg[0];
 -                      $param = $arg[1];
 +                      list( $opt, $param ) = $arg;
  
                        switch ( $opt ) {
                                case 'plugin':