message: [XLA] Augment metadata output with source-line info, as before.
diff: @@ -811,13 +811,25 @@ string HloDotDumper::GetInstructionNodeLabel(const HloInstruction* instr) {
  }
  string HloDotDumper::GetInstructionNodeMetadata(const HloInstruction* instr) {
  - if (!show_metadata_ || instr->metadata().op_name().empty()) {
  + if (!show_metadata_) {
  return "";
  }
  - return Printf(R"(%s<br/>op_type: %s)",
  - HtmlLikeStringSanitize(instr->metadata().op_name()),
  - HtmlLikeStringSanitize(instr->metadata().op_type()));
  + std::vector<string> lines;
  + if (!instr->metadata().op_name().empty()) {
  + lines.push_back(HtmlLikeStringSanitize(instr->metadata().op_name()));
  + }
  + if (!instr->metadata().op_type().empty()) {
  + lines.push_back(Printf(
  + "op_type: %s", HtmlLikeStringSanitize(instr->metadata().op_type())));
  + }
  + if (!instr->metadata().source_file().empty() &&
  + instr->metadata().source_line() != 0) {
  + lines.push_back(Printf("op_type: %s", instr->metadata().source_file(),
  + instr->metadata().source_line()));
  + }
  +
  + return Join(lines, "<br/>");
  }
  string HloDotDumper::GetInstructionNodeExtraInfo(const HloInstruction* instr) {
  