Enqueue: Replaced specific StreamDialogEntry items with one

The enqueue options won't be shown in the dialogs if the Player service is not running. When it's running one item (enqueue stream) will be shown and enqueues the item into the Player type which is currently selected.

app/src/main/java/org/schabi/newpipe/player/helper/PlayerHolder.java

@@ -38,6 +38,8 @@ public final class PlayerHolder {
     /**
      * Returns the current {@link MainPlayer.PlayerType} of the {@link MainPlayer} service,
      * otherwise `null` if no service running.
+     *
+     * @return Current PlayerType
      */
     @Nullable
     public static MainPlayer.PlayerType getType() {