@NotNull
  public Set<LabelColor> getColors() {
    if (labels == null || labels.isEmpty()) {
      return EnumSet.noneOf(LabelColor.class);
    }
    final List<LabelColor> labelColors = ContainerUtil.mapNotNull(labels, label -> {
      final LabelColor color = label.getColor();
      return color == LabelColor.NO_COLOR ? null : color;
    });
    return labelColors.isEmpty() ? EnumSet.noneOf(LabelColor.class) : EnumSet.copyOf(labelColors);
  }
@NotNull
  public Set<LabelColor> getColors()