Primitives · a raise keeps its state under its owner's id

A raise inside another was namespaced by its place in the layer's
queue, so one that came before it moved its id path and rebuilt its
keyed state and focus: an open date popup would lose its month when a
tip appeared. raise now takes its owner's id and draws under it, and
float and float_height pass the owner's id on from every call site.
A test holds a focused box in a raise while another comes before it.

src/overlays/dialog.rs

@@ -271,6 +271,7 @@ impl RenderOnce for Dialog {
             let viewport = window.viewport_size();
             let top = cx.theme().titlebar_height().to_pixels(window.rem_size());
             return raise(
+                (self.id.clone(), "raised"),
                 anchored().position(point(Pixels::ZERO, top)).child(
                     div()
                         .w(viewport.width)