make wxFrame a wxControlContainer too, so that it behaves in the same way as wxDialog

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@46452 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/mac/carbon/window.h

@@ -214,8 +214,13 @@ public:
     // returns true if the grandchildren need to be clipped to the children's content area
     // (e.g., splitter windows)
     virtual bool        MacClipGrandChildren() const { return false ; }
-    bool                MacIsWindowScrollbar( const wxWindow* sb )
+    bool                MacIsWindowScrollbar( const wxWindow* sb ) const
     { return ((wxWindow*)m_hScrollBar == sb || (wxWindow*)m_vScrollBar == sb) ; }
+    virtual bool IsClientAreaChild(const wxWindow *child) const
+    {
+        return !MacIsWindowScrollbar(child) &&
+               wxWindowBase::IsClientAreaChild(child);
+    }
 
     virtual void        MacInstallEventHandler(WXWidget native) ;
     void                MacPostControlCreate(const wxPoint& pos, const wxSize& size) ;