Undefined index in discovered graph configuration

Steps to reproduce:

1. Create host with discovery rule, that has couple item prototypes.
2. Perform discovery for this rule. (discovered items should be created)
3. In discovery rule create graph prototype, that contains both discovered item and prototype item.
4. Perform discovery again.

Result: Undefined index.

Undefined index: name [graphs.php:616 → CView->render() → include() in include/views/configuration.graph.edit.php:71]
Undefined index: itemid [graphs.php:616 → CView->render() → include() in include/views/configuration.graph.edit.php:74]

Expected: No undefined index.