Don't delete previous character when pressing Del at end of buffer.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/branches/WX_2_8_BRANCH@63371 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/richtext/richtextctrl.cpp

@@ -969,7 +969,7 @@ void wxRichTextCtrl::OnChar(wxKeyEvent& event)
                 }
             }
 
-            if (!processed)
+            if (!processed && newPos < (GetLastPosition()-1))
                 GetBuffer().DeleteRangeWithUndo(wxRichTextRange(newPos+1, newPos+1), this);
         }