scripting: Add js object <-> QRectF/QSizeF/QPointF conversion helpers
The js code contains code such as
window.frameGeometry = {x: 42, y: 42, width: 100, height: 50};However, QJSEngine doesn't know how to convert js object to QRect. For that purpose, we need to register conversion functions.
So far, we kept registering converter functions only for integer based geometry types, i.e. QRect, QSize and QPoint. In 5.26, Window was ported to QRectF, QSizeF and QPointF, but the corresponding conversion helpers were not added.