added new fieldset

Author: mahesh-rajawat

app/code/Magento/Quote/Model/Quote/Item/ToOrderItem.php

@@ -64,15 +64,15 @@ public function convert($item, $data = [])
             $item
         );
         if ($item instanceof \Magento\Quote\Model\Quote\Address\Item) {
-            $data = array_merge(
-                $data,
-                $this->objectCopyService->getDataFromFieldset(
-                    'quote_convert_item',
-                    'to_order_item_id',
-                    $item
-                )
-            );
-        }
+            $orderItemData= array_merge(
+                $orderItemData,
+               $this->objectCopyService->getDataFromFieldset(
+                   'quote_convert_address_item',
+                   'to_order_item',
+                   $item
+               )
+           );
+       }
         if (!$item->getNoDiscount()) {
             $data = array_merge(
                 $data,

app/code/Magento/Quote/etc/fieldset.xml

@@ -186,6 +186,11 @@
                 <aspect name="to_order_address" />
             </field>
         </fieldset>
+        <fieldset id="quote_convert_address_item">
+            <field name="quote_item_id">
+                <aspect name="to_order_item" />
+            </field>
+        </fieldset>
         <fieldset id="quote_convert_item">
             <field name="sku">
                 <aspect name="to_order_item" />
@@ -205,9 +210,6 @@
             <field name="qty">
                 <aspect name="to_order_item" targetField="qty_ordered" />
             </field>
-            <field name="quote_item_id">
-                <aspect name="to_order_item_id" targetField="quote_item_id" />
-            </field>
             <field name="id">
                 <aspect name="to_order_item" targetField="quote_item_id" />
             </field>