clear tracks from tracklists before releasing to widget pool

ui/browsing/albumpage.go

@@ -117,6 +117,7 @@ func (a *AlbumPage) Save() SavedPage {
 	s.sort = a.tracklist.Sorting()
 	a.header.page = nil
 	a.pool.Release(util.WidgetTypeAlbumPageHeader, a.header)
+	a.tracklist.Clear()
 	a.pool.Release(util.WidgetTypeTracklist, a.tracklist)
 	return &s
 }

ui/browsing/artistpage.go

@@ -127,6 +127,7 @@ func (a *ArtistPage) Save() SavedPage {
 	if a.tracklistCtr != nil {
 		tl := a.tracklistCtr.Objects[0].(*widgets.Tracklist)
 		s.trackSort = tl.Sorting()
+		tl.Clear()
 		a.pool.Release(util.WidgetTypeTracklist, tl)
 	}
 	a.pool.Release(util.WidgetTypeArtistPageHeader, a.header)

ui/browsing/favoritespage.go

@@ -202,6 +202,7 @@ func (a *FavoritesPage) Save() SavedPage {
 	if a.tracklistCtr != nil {
 		tl := a.tracklistCtr.Objects[0].(*widgets.Tracklist)
 		sf.trackSort = tl.Sorting()
+		tl.Clear()
 		a.pool.Release(util.WidgetTypeTracklist, tl)
 	}
 	return sf

ui/browsing/nowplayingpage.go

@@ -99,6 +99,7 @@ func (a *NowPlayingPage) CreateRenderer() fyne.WidgetRenderer {
 }
 
 func (a *NowPlayingPage) Save() SavedPage {
+	a.tracklist.Clear()
 	a.pool.Release(util.WidgetTypeTracklist, a.tracklist)
 	nps := a.nowPlayingPageState
 	return &nps

ui/browsing/playlistpage.go

@@ -116,6 +116,7 @@ func (a *PlaylistPage) Save() SavedPage {
 	p := a.playlistPageState
 	p.trackSort = a.tracklist.Sorting()
 	p.widgetPool.Release(util.WidgetTypePlaylistPageHeader, a.header)
+	a.tracklist.Clear()
 	p.widgetPool.Release(util.WidgetTypeTracklist, a.tracklist)
 	return &p
 }

ui/browsing/trackspage.go

@@ -151,6 +151,7 @@ func (t *TracksPage) CreateRenderer() fyne.WidgetRenderer {
 
 func (t *TracksPage) Save() SavedPage {
 	t.loader.Dispose()
+	t.tracklist.Clear()
 	t.widgetPool.Release(util.WidgetTypeTracklist, t.tracklist)
 	state := t.tracksPageState
 	return &state