LibGUI: Allow creating a recent-files list without a trailing separator

This is useful in situations where we want this list in a submenu.

Userland/Libraries/LibGUI/Menu.cpp

@@ -224,7 +224,7 @@ void Menu::realize_menu_item(MenuItem& item, int item_id)
     }
 }
 
-void Menu::add_recent_files_list(Function<void(Action&)> callback)
+void Menu::add_recent_files_list(Function<void(Action&)> callback, AddTrailingSeparator add_trailing_separator)
 {
     m_recent_files_callback = move(callback);
 
@@ -244,7 +244,8 @@ void Menu::add_recent_files_list(Function<void(Action&)> callback)
         add_action(action);
     }
 
-    add_separator();
+    if (add_trailing_separator == AddTrailingSeparator::Yes)
+        add_separator();
 }
 
 }

Userland/Libraries/LibGUI/Menu.h

@@ -46,7 +46,11 @@ public:
     [[nodiscard]] NonnullRefPtr<Menu> add_submenu(String name);
     void remove_all_actions();
 
-    void add_recent_files_list(Function<void(Action&)>);
+    enum class AddTrailingSeparator {
+        No,
+        Yes,
+    };
+    void add_recent_files_list(Function<void(Action&)>, AddTrailingSeparator = AddTrailingSeparator::Yes);
 
     void popup(Gfx::IntPoint screen_position, RefPtr<Action> const& default_action = nullptr, Gfx::IntRect const& button_rect = {});
     void dismiss();