Merge remote-tracking branch 'mainline/develop' into BUGS

Author: slavvka

app/code/Magento/Sales/Model/ResourceModel/Order/Item/Collection.php

@@ -55,6 +55,7 @@ protected function _afterLoad()
          * Assign parent items
          */
         foreach ($this as $item) {
+            $this->_resource->unserializeFields($item);
             if ($item->getParentItemId()) {
                 $item->setParentItem($this->getItemById($item->getParentItemId()));
             }

lib/internal/Magento/Framework/Session/SessionManager.php

@@ -470,7 +470,7 @@ public function regenerateId()
             return $this;
         }
         if ($this->isSessionExists()) {
-            session_regenerate_id(true);
+            session_regenerate_id(false);
         } else {
             session_start();
         }