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/navigation/menu.rs

@@ -236,7 +236,14 @@ impl RenderOnce for NavigationMenu {
                 .on_mouse_down_out(move |_, _, cx| show(&close, None, cx))
                 .children(links);
             let rows = entries[entry].1.len().div_ceil(2) * 2;
-            float(state.read(cx).anchors[entry], rows, content, window, cx)
+            float(
+                (self.id.clone(), format!("menu-{entry}")),
+                state.read(cx).anchors[entry],
+                rows,
+                content,
+                window,
+                cx,
+            )
         });
         let (keys, key_entries, enter) = (state.clone(), entries.clone(), pick);
         div()