Pass embedding request to the shortcode rendering controller

Traditionally, you have self-contained shortcodes that carry all information
necessary to render them as parameters. But sometimes, the information is in
the context of the embedding entity. E.g. if you want to embed a list of the
child nodes of the current node in a tree, it's more comfortable to use a short
code like [children] than [children id-of-current-node].

By passing the embedding request to the shortcode rendering controllers, we
allow them to become context sensitive.

Author: MalteWunsch

Handler/EmbeddedShortcodeHandler.php

@@ -71,7 +71,10 @@ public function __invoke(ShortcodeInterface $shortcode)
         );
 
         return $this->fragmentHandler->render(
-            new ControllerReference($this->controllerName, $shortcode->getParameters()),
+            new ControllerReference(
+                $this->controllerName,
+                array_merge(['request' => $this->requestStack->getCurrentRequest()], $shortcode->getParameters())
+            ),
             $this->renderer
         );
     }