tidy avnwindow menu code.

native/Avalonia.Native/src/OSX/menu.mm

@@ -170,31 +170,6 @@ HRESULT AvnAppMenu::Clear()
     return S_OK;
 }
 
-//static IAvnAppMenu* s_AppMenu = nullptr;
-
-/*extern IAvnAppMenu* GetAppMenu()
-{
-    @autoreleasepool
-    {
-        //todo get rid of this method.
-        if(s_AppMenu == nullptr)
-        {
-            id menubar = [NSMenu new];
-            [menubar setTitle:@"Test"];
-            [NSApp setMainMenu:menubar];
-            
-            id appMenuItem = [AvnMenuItem new];
-            [menubar addItem:appMenuItem];
-            
-            [appMenuItem setSubmenu:[AvnMenu new]];
-            
-            s_AppMenu = new AvnAppMenu([[NSApplication sharedApplication] mainMenu]);
-        }
-        
-        return s_AppMenu;
-    }
-}*/
-
 extern IAvnAppMenu* CreateAppMenu()
 {
     @autoreleasepool

native/Avalonia.Native/src/OSX/window.mm

@@ -1096,6 +1096,11 @@ NSArray* AllLoopModes = [NSArray arrayWithObjects: NSDefaultRunLoopMode, NSEvent
 
 -(void) applyMenu:(NSMenu *)menu
 {
+    if(menu == nullptr)
+    {
+        menu = [NSMenu new];
+    }
+    
     _menu = menu;
     [NSApp setMenu:menu];
 }
@@ -1194,13 +1199,11 @@ NSArray* AllLoopModes = [NSArray arrayWithObjects: NSDefaultRunLoopMode, NSEvent
     {
         if(_menu == nullptr)
         {
-            [NSApp setMenu: [NSMenu new]];
-        }
-        else
-        {
-            [NSApp setMenu:_menu];
+            _menu = [NSMenu new];
         }
         
+        [NSApp setMenu:_menu];
+        
         _parent->BaseEvents->Activated();
         [super becomeKeyWindow];
     }