musescore/MuseScore — pull request #98 by vanferry (2012-09-29 01:52:36+00:00)
Title: fix 18226: [MusicXML] Beamed multiple grace notes not beamed

maybe fix:
http://musescore.org/en/node/18226
http://musescore.org/en/node/18288

When get grace segment, first get chordrest segment at tick, then search backwards for its graces. If there is already grace segment, do not create it.