Implements \Drupal\Component\Plugin\PluginBag::initializePlugin().
Overrides PluginBag::initializePlugin
protected function initializePlugin($instance_id) {
// If the plugin was initialized before, just return.
if (isset($this->pluginInstances[$instance_id])) {
return;
}
$this->pluginInstances[$instance_id] = $this->manager
->createInstance($instance_id, array());
}