Issue #3487586 by geek-merlin: BlockLibraryController typehints...

use Drupal\Core\Controller\ControllerBase;

use Drupal\Core\EventSubscriber\MainContentViewSubscriber;

use Drupal\Core\Menu\LocalActionManagerInterface;

use Drupal\Core\Plugin\Context\LazyContextRepository;

use Drupal\Core\Plugin\Context\ContextRepositoryInterface;

use Drupal\Core\Routing\RouteMatchInterface;

use Drupal\Core\Url;

use Symfony\Component\DependencyInjection\ContainerInterface;

use Symfony\Component\HttpFoundation\Request;

/**

   *

   * @param \Drupal\Core\Block\BlockManagerInterface $block_manager

   *   The block manager.

   * @param \Drupal\Core\Plugin\Context\LazyContextRepository $context_repository

   * @param \Drupal\Core\Plugin\Context\ContextRepositoryInterface $context_repository

   *   The context repository.

   * @param \Drupal\Core\Routing\RouteMatchInterface $route_match

   *   The current route match.

   * @param \Drupal\Core\Menu\LocalActionManagerInterface $local_action_manager

   *   The local action manager.

   */

  public function __construct(BlockManagerInterface $block_manager, LazyContextRepository $context_repository, RouteMatchInterface $route_match, LocalActionManagerInterface $local_action_manager) {

  public function __construct(BlockManagerInterface $block_manager, ContextRepositoryInterface $context_repository, RouteMatchInterface $route_match, LocalActionManagerInterface $local_action_manager) {

    $this->blockManager = $block_manager;

    $this->routeMatch = $route_match;

    $this->localActionManager = $local_action_manager;

    $this->contextRepository = $context_repository;

  }

  /**

   * {@inheritdoc}

   */

  public static function create(ContainerInterface $container) {

    return new static(

      $container->get('plugin.manager.block'),

      $container->get('context.repository'),

      $container->get('current_route_match'),

      $container->get('plugin.manager.menu.local_action')

    );

  }

  /**

   * Shows a list of blocks that can be added to a theme's layout.

   *