Wrong panel display assigned to page with different context on import context

Added patch. It should handle all cases, when source and destination context have/have no panels with IPE attached.

In case you need to fix already imported pages from different contexts.

**
 * Fix wrong panel displays for config pages.
 */
function MODULE_NAME_update_7001() {
  // Locate any displays associated with the config_pages entities.
  $query = db_select('panelizer_entity', 'pe')
    ->fields('pe', ['entity_id', 'did'])
    ->condition('entity_type', 'config_pages')
    ->execute()
    ->fetchAll();

  // List for entities referencing the same display IDs.
  $dids = [];
  foreach ($query as $row) {
    $dids[$row->did][] = $row->entity_id;
  }

  $panelizer_handler = panelizer_entity_plugin_get_handler('config_pages');
  foreach ($dids as $entity_ids) {
    $count = count($entity_ids);
    if ($count == 1) {
      continue;
    }

    // Take the first display and clone it for the needed entities.
    $config_first = config_pages_load($entity_ids[0]);
    for ($i = 1; $i < $count; $i++) {
      $config = config_pages_load($entity_ids[$i]);
      // Delete wrongly assigned panel displays.
      /** @var PanelizerEntityConfigPages $panelizer_handler */
      $panelizer_handler->delete_entity_panelizer($config);
      // Copy panelizer, mark as modified, cloning will be handled by panels.
      $config->panelizer = $config_first->panelizer;
      foreach ($config->panelizer as $view_mode => $panelizer) {
        $panelizer->display_is_modified = TRUE;
        $panelizer->entity_id = NULL;
      }

      config_pages_save($config);
    }

    // Fix the first entity, it can also have wrong IDs, clone from the last.
    $config = config_pages_load($config->config_pages_id);
    $panelizer_handler->delete_entity_panelizer($config_first);
    $config_first->panelizer = $config->panelizer;
    foreach ($config_first->panelizer as $view_mode => $panelizer) {
      $panelizer->display_is_modified = TRUE;
      $panelizer->entity_id = NULL;
    }
    config_pages_save($config_first);
  }
}