  String DumpFragmentTree(const NGPhysicalBoxFragment* fragment) {
    NGPhysicalFragment::DumpFlags flags =
        NGPhysicalFragment::DumpHeaderText | NGPhysicalFragment::DumpSubtree |
        NGPhysicalFragment::DumpIndentation | NGPhysicalFragment::DumpOffset |
        NGPhysicalFragment::DumpSize;

    return fragment->DumpFragmentTree(flags);
  }

Unknown