MAGETWO-91666: Wishlist update does not return a success message

- Added message about successful saving of the product description on Wish list page

Author: Nikita Chubukov

app/code/Magento/Wishlist/Controller/Index/Update.php

@@ -111,6 +111,9 @@ public function execute()
                 }
                 try {
                     $item->setDescription($description)->setQty($qty)->save();
+                    $this->messageManager->addSuccessMessage(
+                        __('%1 has been updated in your Wish List.', $item->getProduct()->getName())
+                    );
                     $updatedItems++;
                 } catch (\Exception $e) {
                     $this->messageManager->addError(