Passed to PlaylistDumpList by PlaylistDetail, from usePlaylist.
The calls are given only to those who may edit the playlist.
optional
onRemove: (dumpId: string) => void
optional
onUndoRemove: (dumpId: string) => void
optional
onMove: (from: number,to: number) => void
Counts only the dumps not fading, which alone can be dragged.
optional
onMoved: () => void
Called as a drag ends, to save the order onMove left.