@Override
  public @NotNull InputDataDiffBuilder<Integer, SerializedStubTree> createDiffBuilderByMap(int inputId,
                                                                                           @Nullable Map<Integer, SerializedStubTree> data)
    throws IOException {
    SerializedStubTree tree = ContainerUtil.isEmpty(data) ? null : ContainerUtil.getFirstItem(data.values());
    if (tree != null) {
      tree.restoreIndexedStubs();
    }
    return new StubCumulativeInputDiffBuilder(inputId, tree);
  }
@Override
  public @NotNull InputDataDiffBuilder<Integer, SerializedStubTree> createDiffBuilderByMap(int inputId,
                                                                                           @Nullable Map<Integer, SerializedStubTree> data)