Layouts are unnecessarily strict about anchor usage

Layouts presently restrict any use of anchors by children, with the following message: "Detected anchors on an item that is managed by a layout. This is undefined behaviour; use Layout.alignment instead"

While I can understand that such a warning makes sense, it is overly strict, and (particularly in the case of 'baseline', which does not have an appropriate replacement in 'alignment' terms), restrictive.

I think that the more correct thing to do would be something like QQuickAnchorsPrivate::checkHValid: check that the set anchor "directions" do not conflict with the layout's settings.

See the code below for an example.

import QtQuick 2.6
import QtQuick.Layouts 1.2

Item {
    RowLayout {
        Rectangle {
            id: marker
            width: 10
            height: 10
            color: "red"
        }

        Text {
            anchors.baseline: marker.verticalCenter
            text: "Hello, world"
        }
    }
}