work towards shifting functions from timelineview to timelinewidget

app/widget/timelineview/timelineviewrect.cpp

@@ -52,12 +52,12 @@ void TimelineViewRect::SetHeight(const int &height)
   UpdateRect();
 }
 
-const int &TimelineViewRect::Track()
+const TrackReference &TimelineViewRect::Track()
 {
   return track_;
 }
 
-void TimelineViewRect::SetTrack(const int &track)
+void TimelineViewRect::SetTrack(const TrackReference &track)
 {
   track_ = track;
 }