Fix importFromArray by setting _isCollectionLoaded to true after import

Author: slackerzz

app/code/Magento/Eav/Model/Entity/Collection/AbstractCollection.php

@@ -1061,6 +1061,7 @@ public function importFromArray($arr)
                 $this->_items[$entityId]->addData($row);
             }
         }
+        $this->_setIsLoaded();
         return $this;
     }