Issue #1889748 by tim.plunkett: Figure out what to do with ConfigMapper.

core/lib/Drupal/Core/Plugin/Mapper/ConfigMapper.php

-<?php
-
-/**
- * @file
- * Contains \Drupal\Core\Plugin\Mapper\ConfigMapper.
- */
-
-namespace Drupal\Core\Plugin\Mapper;
-
-use Drupal\Component\Plugin\Mapper\MapperInterface;
-use Drupal\Component\Plugin\PluginManagerInterface;
-use Drupal\Component\Plugin\Exception\PluginException;
-
-/**
- * Retrieves plugin instances from the configuration system.
- */
-class ConfigMapper implements MapperInterface {
-
-  /**
-   * The plugin manager instance used by this mapper.
-   *
-   * @var \Drupal\Component\Plugin\PluginManagerInterface
-   */
-  protected $manager;
-
-  /**
-   * Constructs a \Drupal\Core\Plugin\Mapper\ConfigMapper object.
-   *
-   * @param \Drupal\Component\Plugin\PluginManagerInterface $manager
-   *   The plugin manager instance to use for this mapper.
-   */
-  public function __construct(PluginManagerInterface $manager) {
-    $this->manager = $manager;
-  }
-
-  /**
-   * Implements \Drupal\Component\Plugin\Mapper\MapperInterface::getInstance().
-   */
-  public function getInstance(array $options) {
-    $config = config($options['config']);
-    if ($config) {
-      $plugin_id = $config->get('id');
-      $settings = $config->get();
-      $settings['config_id'] = $options['config'];
-      // Attempt to create an instance with this plugin ID and settings.
-      try {
-        return $this->manager->createInstance($plugin_id, $settings);
-      }
-      catch (PluginException $e) {
-        return FALSE;
-      }
-    }
-    return FALSE;
-  }
-
-}