MAGETWO-35620: Implement Observer

Author: Dmytro Voskoboinikov

app/code/Magento/Sales/Controller/Adminhtml/Order/Creditmemo/Save.php

@@ -95,9 +95,10 @@ public function execute()
                         isset($data['comment_customer_notify']),
                         isset($data['is_visible_on_front'])
                     );
+
+                    $creditmemo->setCustomerNote($data['comment_text']);
                 }
 
-                $creditmemo->setCustomerNote($data['comment_text']);
                 $creditmemo->setCustomerNoteNotify(isset($data['comment_customer_notify']));
 
                 if (isset($data['do_refund'])) {

app/code/Magento/Sales/Controller/Adminhtml/Order/Invoice/Save.php

@@ -158,9 +158,10 @@ public function execute()
                     isset($data['comment_customer_notify']),
                     isset($data['is_visible_on_front'])
                 );
+
+                $invoice->setCustomerNote($data['comment_text']);
             }
 
-            $invoice->setCustomerNote($data['comment_text']);
             $invoice->setCustomerNoteNotify(isset($data['comment_customer_notify']));
 
             $invoice->register();

app/code/Magento/Shipping/Controller/Adminhtml/Order/Shipment/Save.php

@@ -106,9 +106,10 @@ public function execute()
                     isset($data['comment_customer_notify']),
                     isset($data['is_visible_on_front'])
                 );
+
+                $shipment->setCustomerNote($data['comment_text']);
             }
 
-            $shipment->setCustomerNote($data['comment_text']);
             $shipment->setCustomerNoteNotify(isset($data['comment_customer_notify']));
 
             $shipment->register();