ComboBox: warning when model is not ready

import QtQuick 2.1
import QtQuick.Controls 1.0

Rectangle {
    width: 360
    height: 360
    ComboBox {
        model: model
        textRole: 'name'
    }
    ListModel {
        id: model
        Component.onCompleted: {
            append({ name: "Button", age: 12});
            append({ name: "ToolButton", age: 12});
            append({ name: "CheckBox", age: 12});
        }
    }
}