Revert "Show indicator on current playing song. Fixes #128"

This implementation causes performance issues

ui/src/album/AlbumSongs.js

@@ -2,6 +2,7 @@ import React from 'react'
 import {
   BulkActionsToolbar,
   DatagridLoading,
+  FunctionField,
   ListToolbar,
   TextField,
   useListController,
@@ -14,10 +15,9 @@ import StarBorderIcon from '@material-ui/icons/StarBorder'
 import { playTracks } from '../audioplayer'
 import {
   DurationField,
-  SongContextMenu,
-  SongDatagrid,
   SongDetails,
-  SongTitleField,
+  SongDatagrid,
+  SongContextMenu,
 } from '../common'
 import AddToPlaylistDialog from '../dialogs/AddToPlaylistDialog'
 
@@ -62,6 +62,14 @@ const useStylesListToolbar = makeStyles({
   },
 })
 
+const trackName = (r) => {
+  const name = r.title
+  if (r.trackNumber) {
+    return r.trackNumber.toString().padStart(2, '0') + ' ' + name
+  }
+  return name
+}
+
 const AlbumSongs = (props) => {
   const classes = useStyles(props)
   const classesToolbar = useStylesListToolbar(props)
@@ -124,11 +132,14 @@ const AlbumSongs = (props) => {
                   sortable={false}
                 />
               )}
-              <SongTitleField
-                source="title"
-                sortable={false}
-                showTrackNumbers={!isDesktop}
-              />
+              {isDesktop && <TextField source="title" sortable={false} />}
+              {!isDesktop && (
+                <FunctionField
+                  source="title"
+                  render={trackName}
+                  sortable={false}
+                />
+              )}
               {isDesktop && <TextField source="artist" sortable={false} />}
               <DurationField source="duration" sortable={false} />
               <SongContextMenu