Issue #2889684 by ankitjain28may, kanav_7, borisson_, gaurav.kapoor,...

Issue #2889684 by ankitjain28may, kanav_7, borisson_, gaurav.kapoor, naveenvalecha, joachim, alexpott: missing class docs for ContainerDerivativeDiscoveryDecorator

core/lib/Drupal/Core/Plugin/Discovery/ContainerDerivativeDiscoveryDecorator.php

@@ -4,6 +4,11 @@
 
 use Drupal\Component\Plugin\Discovery\DerivativeDiscoveryDecorator;
 
+/**
+ * Injects dependencies into derivers if they use ContainerDeriverInterface.
+ *
+ * @see \Drupal\Core\Plugin\Discovery\ContainerDeriverInterface
+ */
 class ContainerDerivativeDiscoveryDecorator extends DerivativeDiscoveryDecorator {
 
   /**