Regression: <center> tag no longer centers rich text

import QtQuick 2.0

Item {
    width: 800
    height: 400

    Text {
        textFormat: Text.RichText
        text: "<center>First line<br>----- Second line -----</center>"
        anchors.centerIn: parent
        color: "white"
        width: 300

        Rectangle {
            anchors.fill: parent
            z: -1
            color: "blue"
        }
    }
}