Playlists: Remove API validation for empty playlists and remove redundant API call (#26982)

* Remove validation from empty playlists

* Remove redundant API call

Frontend used to call /api/playlists/:id/items directly after /api/playlists/:id but items are already included in the first response

pkg/api/playlist.go

 package api
 
 import (
-	"net/http"
-
 	"github.com/grafana/grafana/pkg/bus"
 	"github.com/grafana/grafana/pkg/models"
 )
@@ -26,18 +24,6 @@ func ValidateOrgPlaylist(c *models.ReqContext) {
 		c.JsonApiErr(403, "You are not allowed to edit/view playlist", nil)
 		return
 	}
-
-	items, itemsErr := LoadPlaylistItemDTOs(id)
-
-	if itemsErr != nil {
-		c.JsonApiErr(404, "Playlist items not found", err)
-		return
-	}
-
-	if len(items) == 0 && c.Context.Req.Method != http.MethodDelete {
-		c.JsonApiErr(404, "Playlist is empty", itemsErr)
-		return
-	}
 }
 
 func SearchPlaylists(c *models.ReqContext) Response {

public/app/features/playlist/playlist_edit_ctrl.ts

@@ -46,14 +46,7 @@ export class PlaylistEditCtrl {
           .get('/api/playlists/' + playlistId)
           .then((result: any) => {
             this.playlist = result;
-          })
-      );
-
-      promiseToDigest(this.$scope)(
-        getBackendSrv()
-          .get('/api/playlists/' + playlistId + '/items')
-          .then((result: any) => {
-            this.playlistItems = result;
+            this.playlistItems = result.items;
           })
       );
     }