chore: reduce component overhead (#3)

Reviewed-on: reya/gpui-native-kit#3

crates/core/src/dropdown_menu.rs

@@ -7,7 +7,7 @@ use gpui::prelude::FluentBuilder as _;
 use gpui::{
     App, ClickEvent, DispatchPhase, ElementId, InteractiveElement as _, IntoElement, KeyDownEvent,
     MouseButton, MouseDownEvent, ParentElement as _, RenderOnce, Role, SharedString,
-    StatefulInteractiveElement as _, Styled as _, Window, canvas, div, hsla, relative,
+    StatefulInteractiveElement as _, Styled as _, Window, canvas, div, relative,
 };
 use gpui_native_icons::{IconRole, icon};
 use gpui_native_theme::{ActiveTheme as _, BORDER_WIDTH, Size};
@@ -193,7 +193,7 @@ impl RenderOnce for DropdownMenu {
         let border = if show_border {
             colors.border
         } else {
-            background.unwrap_or_else(|| hsla(0.0, 0.0, 0.0, 0.0))
+            background.unwrap_or_else(gpui::transparent_black)
         };
 
         let split = self.on_click.is_some();
@@ -207,7 +207,8 @@ impl RenderOnce for DropdownMenu {
         let a11y_label = self.a11y_label.or_else(|| self.label.clone());
         let focus = focus_handle(&self.id, window, cx).tab_stop(self.tab_stop);
         // How the menu was last opened, read by the frame that mounts the panel.
-        let keyboard_open = window.use_keyed_state("dropdown-open-origin", cx, |_, _| false);
+        let keyboard_open =
+            window.use_keyed_state((self.id.clone(), "dropdown-open-origin"), cx, |_, _| false);
 
         let on_open: ChangeHandler = {
             let focus = focus.clone();
@@ -421,10 +422,10 @@ impl RenderOnce for DropdownMenu {
 
         let items = if self.open {
             self.items
-                .map(|build| build(window, cx))
-                .unwrap_or_default()
+                .map(|build| Rc::from(build(window, cx)))
+                .unwrap_or_else(|| Rc::from([]))
         } else {
-            Vec::new()
+            Rc::from([])
         };
 
         if let Some(panel) = anchored_menu_panel(