Issue #3317243 by mondrake: Fix PluginManagerBase PHPStan-0 issues

   *

   * @return object

   *   A fallback plugin instance.

   *

   * @throws \BadMethodCallException

   *   When ::getFallbackPluginId() is not implemented in the concrete plugin

   *   manager class.

   */

  protected function handlePluginNotFound($plugin_id, array $configuration) {

    $fallback_id = $this->getFallbackPluginId($plugin_id, $configuration);

    return $this->getFactory()->createInstance($fallback_id, $configuration);

  }

  /**

   * Gets a fallback id for a missing plugin.

   *

   * This method should be implemented in extending classes that also implement

   * FallbackPluginManagerInterface. It is called by

   * PluginManagerBase::handlePluginNotFound on the abstract class, and

   * therefore should be defined as well on the abstract class to prevent static

   * analysis errors.

   *

   * @param string $plugin_id

   *   The ID of the missing requested plugin.

   * @param array $configuration

   *   An array of configuration relevant to the plugin instance.

   *

   * @return string

   *   The id of an existing plugin to use when the plugin does not exist.

   *

   * @throws \BadMethodCallException

   *   If the method is not implemented in the concrete plugin manager class.

   */

  protected function getFallbackPluginId($plugin_id, array $configuration = []) {

    throw new \BadMethodCallException(get_class() . '::getFallbackPluginId() not implemented.');

  }

  /**

   * {@inheritdoc}

   */

			count: 1

			path: lib/Drupal/Component/Gettext/PoMemoryWriter.php

		-

			message: "#^Call to an undefined method Drupal\\\\Component\\\\Plugin\\\\PluginManagerBase\\:\\:getFallbackPluginId\\(\\)\\.$#"

			count: 1

			path: lib/Drupal/Component/Plugin/PluginManagerBase.php

		-

			message: "#^Method Drupal\\\\Core\\\\Access\\\\CsrfRequestHeaderAccessCheck\\:\\:applies\\(\\) should return bool but return statement is missing\\.$#"

			count: 1