<webview>, <appview> and <extensionoptions> can run in a detached state.

extensions/browser/guest_view/app_view/app_view_guest.h

Index: extensions/browser/guest_view/app_view/app_view_guest.h
diff --git a/extensions/browser/guest_view/app_view/app_view_guest.h b/extensions/browser/guest_view/app_view/app_view_guest.h
index e1bc1faf246439ac272e655c666e9ff488208f14..f745b4896410a910d67837cded65493e8aab40c0 100644
--- a/extensions/browser/guest_view/app_view/app_view_guest.h
+++ b/extensions/browser/guest_view/app_view/app_view_guest.h
@@ -53,12 +53,12 @@ class AppViewGuest : public GuestView<AppViewGuest>,
                                   content::MediaStreamType type) override;
 
   // GuestViewBase implementation.
-  const char* GetAPINamespace() const override;
-  int GetTaskPrefix() const override;
+  bool CanRunInDetachedState() const override;
   void CreateWebContents(const base::DictionaryValue& create_params,
                          const WebContentsCreatedCallback& callback) override;
-  void DidAttachToEmbedder() override;
   void DidInitialize(const base::DictionaryValue& create_params) override;
+  const char* GetAPINamespace() const override;
+  int GetTaskPrefix() const override;
 
   // Sets the AppDelegate for this guest.
   void SetAppDelegateForTest(AppDelegate* delegate);