we are always compositing on the supported OS versions

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@40558 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/mac/carbon/toplevel.h

@@ -99,7 +99,6 @@ public:
 
     virtual void MacSetBackgroundBrush( const wxBrush &brush ) ;
 
-    bool MacUsesCompositing() { return m_macUsesCompositing; }
     virtual void MacInstallTopLevelWindowEventHandler() ;
 
     bool MacGetMetalAppearance() const ;
@@ -126,7 +125,6 @@ protected:
     // should the frame be maximized when it will be shown? set by Maximize()
     // when it is called while the frame is hidden
     bool m_maximizeOnShow;
-    bool m_macUsesCompositing ;
  
     WXWindow m_macWindow ;