@NotNull
  private static Set<GrVariable> buildVarSet(@NotNull List<? extends GrField> fields, boolean isStatic) {
    Set<GrVariable> result = new HashSet<>();
    for (GrField field : fields) {
      if (field.hasModifierProperty(PsiModifier.STATIC) == isStatic) {
        result.add(field);
      }
    }
    return result;
  }
@NotNull
  private static Set<GrVariable> buildVarSet(@NotNull List<? extends GrField> fields, boolean isStatic)