rewrite Self_alignment_interface

lily/multi-measure-rest-engraver.cc

 /*
   This file is part of LilyPond, the GNU music typesetter.
 
   Copyright (C) 1998--2012 Jan Nieuwenhuizen <janneke@gnu.org>
   Han-Wen Nienhuys <hanwen@xs4all.nl>
 
   LilyPond is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.
@@ skipping 128 matching lines @@
                       last = numbers_[i];
                     }
                 }
             }
         }
 
       for (vsize i = 0; i < numbers_.size (); i++)
         {
           Side_position_interface::add_support (numbers_[i], mmrest_);
           numbers_[i]->set_parent (mmrest_, Y_AXIS);
+          // we need a special case in Spanner::set_bound
+          // to avoid overwriting this (FIXME? --jw)
+          numbers_[i]->set_parent (mmrest_, X_AXIS);
         }
 
       start_measure_
         = scm_to_int (get_property ("internalBarNumber"));
     }
 
   bar_seen_ = bar_seen_ || scm_is_string (get_property ("whichBar"));
 }
 
 void
@@ skipping 111 matching lines @@
 
                 /* read */
                 "internalBarNumber "
                 "restNumberThreshold "
                 "currentCommandColumn "
                 "measurePosition ",
 
                 /* write */
                 ""
                );