Incorrect array index given in example for hook_views_ajax_data_alter().

API page: http://api.drupal.org/api/views/views.api.php/function/hook_views_ajax_d...

Inside the foreach loop shown as an example for this function command should be used as the a key and not method, method is not a defined index of the $commands array.

For example
This:

foreach ($commands as $command) {
    if ($command['method'] == 'viewsScrollTop') {
      $command['method'] .= 'myScrollTop';
    }
  }

Should be:

foreach ($commands as $command) {
    if ($command['command'] == 'viewsScrollTop') {
      $command['command'] .= 'myScrollTop';
    }
  }

Isssue posted for drupal8 - https://drupal.org/node/1887892