Qt WebEngine reports wrong UIAutomation bounding rects with high DPI

Issue description

See attached screenshots, taken on a machine with 125% scaling (2560x1440 resolution). UIAutomation inspection was done using Visual UI Automation Verify. 

• Google Chrome reports the correct bounding rect
• WebEngineView on Qt 6.3.0-beta2 reports the wrong bounding rect

Issue scope

• This issue affects both the QML WebEngineView and the widget QWebEngineView.
• It does not seem to affect Qt Quick Controls.
• For Qt 5.15.8, this issue manifests if scaling=200%, but not if scaling=125% or 150% (tested at 3840x2160 resolution).

Example code

import QtQuick 2.15
import QtQuick.Window 2.15
import QtWebEngine 1.10

Window {
    width: 800
    height: 600
    visible: true
    title: "WebEngine UIAutomation"

    WebEngineView {
        anchors.fill: parent
        url: "https://www.google.com"
    }
}