make Scroll() itself virtual too as existing code might override it (but new code should override DoScroll() only); use the same access in the derived classes as in wxScrollHelperBase

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@57538 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/generic/scrolwin.h

@@ -23,11 +23,12 @@ public:
     // implement base class pure virtuals
     virtual void AdjustScrollbars();
 
-private:
+protected:
     virtual void DoScroll(int x, int y);
     virtual void DoShowScrollbars(wxScrollbarVisibility horz,
                                   wxScrollbarVisibility vert);
 
+private:
     // helper of AdjustScrollbars(): does the work for the single scrollbar
     //
     // notice that the parameters passed by non-const references are modified