Get app menus basically working

- Everything is still disabled when there is no active window.

Co-Authored-By: Marshall <marshall@zed.dev>

crates/gpui2/src/platform/test/platform.rs

@@ -1,6 +1,7 @@
 use crate::{
-    AnyWindowHandle, BackgroundExecutor, ClipboardItem, CursorStyle, DisplayId, ForegroundExecutor,
-    Platform, PlatformDisplay, PlatformTextSystem, TestDisplay, TestWindow, WindowOptions,
+    AnyWindowHandle, BackgroundExecutor, ClipboardItem, CursorStyle, DispatchTree, DisplayId,
+    ForegroundExecutor, Platform, PlatformDisplay, PlatformTextSystem, TestDisplay, TestWindow,
+    WindowOptions,
 };
 use anyhow::{anyhow, Result};
 use collections::VecDeque;
@@ -205,6 +206,10 @@ impl Platform for TestPlatform {
         unimplemented!()
     }
 
+    fn set_menus(&self, _menus: Vec<crate::Menu>, _dispatch_tree: Option<&DispatchTree>) {
+        unimplemented!()
+    }
+
     fn on_app_menu_action(&self, _callback: Box<dyn FnMut(&dyn crate::Action)>) {
         unimplemented!()
     }