Regression: program crash in QQuickItem destructor when layouts contain custom property

import QtQuick 2.7
import QtQuick.Controls 2.0
import QtQuick.Layouts 1.3

ApplicationWindow {
    visible: true
    width: 640; height: 480

    ColumnLayout {
        anchors.fill: parent
        RowLayout {
            Layout.alignment: Qt.AlignCenter
            Button {
                text: 'first page'
                onClicked: __stackLayout.currentIndex = 0
            }
            Button {
                text: 'second page'
                onClicked: __stackLayout.currentIndex = 1
            }
        }

        StackLayout {
            id: __stackLayout
            Layout.fillHeight: true; Layout.fillWidth: true

            ListView {
                model: 50
                delegate: __delegate
                Layout.fillHeight: true; Layout.fillWidth: true
            }

            ListView {
                model: 70
                delegate: __delegate
                Layout.fillHeight: true; Layout.fillWidth: true
            }
        }
    }

    Component {
        id: __delegate
        ColumnLayout {
            property bool bug: true

            /* IF REMOVE PROPERTY 'bug' OR REMOVE layout '__childLayout'
               CRASH WILL DISAPPEAR. */

            width: ListView.view.width
            RowLayout {
                id: __childLayout
                Layout.alignment: Qt.AlignCenter
                Text {
                    text: 'This is row № '
                    Layout.fillHeight: true
                }
                Text {
                    text: index; Layout.fillHeight: true
                }
            }
            Rectangle {
                height: 1; color: 'red'
                Layout.fillWidth: true
            }
        }
    }
}