Adds registered custom properties to the dropdown menus, which can be set in another stylesheet at any level (either on the direct element or on an ancestor) or use the default values given.
The styling in the dropdown.less file targeting `.menu-wrapper` was not doing anything. Double checked on old firefox, too, in case it was needed for oddbird polyfill.
revert commit 1fe19578c2 which changed `anchor()` values to `position-area`.
I'm not sure what compelled me to do that change initially, except the easier to understand syntax. Hopefully it wasn't important.
But oddbird polyfill expects `anchor()` values, which it converts to pixel values for positioning.
This updates the position try results by using a different method of setting the area of the anchored element. Rather than using the inset properties with `anchor()`, it uses `position-area`.
Gazook89