The type of thep property is `Point`, which existed before. It was
mapped to `slint::private_unstable_api::re_exports::Point` (euclid) and
is now mapped to slint::LogicalPosition (also in C++).
So that we don't need to query the geometry multiple time, and this pave
the way to not have the geometry in the items
Part of #1932
As a drive by, fix the clipping of the Path element which incorrectly
offseted the clip by (x,y).
Similar fixes happen in the Clip element in some renderer, but that
didn't have effect because x and y are always 0 for the Clip element
Their choice of i16 is specific to the software renderer. In say the Skia renderer
the physical coordinate space would still use Skia's Scalar (floating points).