make IsEnabled() return false even if the window parent, and not the window itself, is disabled and added IsThisEnabled() implementing the old IsEnabled() behaviour; also significantly simplify the window state management code in all ports by factoring out the common parts in wxWindowBase

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@45031 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/mac/carbon/window.h

@@ -55,7 +55,8 @@ public:
     virtual void Lower();
 
     virtual bool Show( bool show = true );
-    virtual bool Enable( bool enable = true );
+    virtual void DoEnable( bool enable );
+    virtual void OnEnabled( bool enabled );
 
     virtual void SetFocus();
 
@@ -310,7 +311,6 @@ protected:
     void                MacUpdateControlFont() ;
 
     void                MacPropagateVisibilityChanged() ;
-    void                MacPropagateEnabledStateChanged() ;
     void                MacPropagateHiliteChanged() ;
 
     // implement the base class pure virtuals