Simplify to return main window even in editor.

Source/Engine/Engine/Screen.cpp

@@ -183,11 +183,7 @@ void Screen::SetGameWindowMode(GameWindowMode windowMode)
 
 Window* Screen::GetMainWindow()
 {
-    Window* win = nullptr;
-#if !USE_EDITOR
-    win = Engine::MainWindow;
-#endif
-    return win;
+    return Engine::MainWindow;
 }
 
 void ScreenService::Update()

Source/Engine/Engine/Screen.h

@@ -98,7 +98,7 @@ DECLARE_SCRIPTING_TYPE_NO_SPAWN(Screen);
     API_PROPERTY() static void SetGameWindowMode(GameWindowMode windowMode);
 
     /// <summary>
-    /// Gets the main window. Only during built game.
+    /// Gets the main window.
     /// </summary>
     /// <returns>The current window. Will be null if fails.</returns>
     API_PROPERTY() static Window* GetMainWindow();