Add title tag and lang attribute to iframe for accessibility

I merged the MR
But followed up with the Full testing round

Having the following may hit a performance issue in projects, If we have 10-20 iframe(s) in the same page
As this will call the resource server ( Youtube, Vimeo, ... ) to get the title from the remote server.
On every load for the page.

  // Add media title from resource if available.
  if (!empty($variables['resource']) && !empty($variables['resource']->getTitle())) {
    $variables['media_title'] = $variables['resource']->getTitle();
  }

Maybe - better to remove this.
I do not recommend using a local patch for this MR in projects.

We had a case before, but was managed with hook_entity_presave

• #3115391: Fix performance issue on page load for calling provider name for each remote video
• #3125946: Fix missing varbase media entity presave hook for remote videos with fullback options

/**
 * Implements hook_entity_presave().
 */
function varbase_media_entity_presave(EntityInterface $entity) {
  if ($entity->getEntityType()->id() == 'media' && $entity->bundle->target_id == 'remote_video') {
    // If the field_provider exists in the remote video media type.
    $field_field_media_remote_video_field_provider = FieldConfig::loadByName('media', 'remote_video', 'field_provider');
    if (isset($field_field_media_remote_video_field_provider)) {
      // Fetch the resource from the URL and save in the field_provider.
      $url_resolver = \Drupal::service('media.oembed.url_resolver');
      $resource_fetcher = \Drupal::service('media.oembed.resource_fetcher');
      $resource_url = $url_resolver->getResourceUrl(($entity->field_media_oembed_video->value));
      $resource = $resource_fetcher->fetchResource($resource_url);
      $provider = strtolower($resource->getProvider()->getName() ?? '');
      if ($entity->field_provider->value != $provider) {
        $entity->set('field_provider', $provider);
      }
    }
  }
}

Easy direction to remove the Add media title from resource if available. ( as we do not want to have any new cache buffer fields )

➖ Performance
Having this will bring a performance issue.

One more option:

• Get the media entity title/name, the one the user/editor filled in when added the remote media.

Hello, some small comments
- Duplicate checks for langcodes, remove logic from twig
- Use media entity label instead of OEmbed to allow admins to edit and translate

✅ Released varbase_media-10.1.2