feat: use default-app behavior in packaged apps (#16310)

Unify the behavior between default app and packaged apps:
- create default application menu unless the app has one
- default window-all-closed handling unless the app handles the event

lib/browser/init.js

@@ -184,5 +184,17 @@ if (currentPlatformSupportsAppIndicator()) {
   process.env.XDG_CURRENT_DESKTOP = 'Unity'
 }
 
+// Quit when all windows are closed and no other one is listening to this.
+app.on('window-all-closed', () => {
+  if (app.listenerCount('window-all-closed') === 1) {
+    app.quit()
+  }
+})
+
+const { setDefaultApplicationMenu } = require('@electron/internal/browser/default-menu')
+
+// Create default menu.
+app.once('ready', setDefaultApplicationMenu)
+
 // Finally load app's main.js and transfer control to C++.
 Module._load(path.join(packagePath, mainStartupScript), Module, true)