make GTKNeedsParent() private

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@73310 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk/window.h

@@ -184,11 +184,6 @@ public:
     static wxLayoutDirection GTKGetLayout(GtkWidget *widget);
     static void GTKSetLayout(GtkWidget *widget, wxLayoutDirection dir);
 
-    // return true if this window must have a non-NULL parent, false if it can
-    // be created without parent (normally only top level windows but in wxGTK
-    // there is also the exception of wxMenuBar)
-    virtual bool GTKNeedsParent() const { return !IsTopLevel(); }
-
     // This is called when capture is taken from the window. It will
     // fire off capture lost events.
     void GTKReleaseMouseAndNotify();
@@ -404,6 +399,11 @@ protected:
 private:
     void Init();
 
+    // return true if this window must have a non-NULL parent, false if it can
+    // be created without parent (normally only top level windows but in wxGTK
+    // there is also the exception of wxMenuBar)
+    virtual bool GTKNeedsParent() const { return !IsTopLevel(); }
+
     enum ScrollUnit { ScrollUnit_Line, ScrollUnit_Page, ScrollUnit_Max };
 
     // common part of ScrollLines() and ScrollPages() and could be used, in the