message: [XLA] Use \n rather than <br/> for linebreaks in graphviz tooltips.
  <br/> doesn't work in this context, but \n does.
diff: @@ -1110,7 +1110,7 @@ string HloDotDumper::GetInstructionNodeMetadata(const HloInstruction* instr) {
  instr->metadata().source_line()));
  }
  - return StrJoin(lines, "<br/>");
  + return StrJoin(lines, "\n");
  }
  string HloDotDumper::GetInstructionNodeBackendConfig(
  