message: [SavedModel C++] Avoid copying the MetaGraphDef in FindMetaGraphDef().
diff: @@ -48,12 +48,12 @@ Status ReadSavedModel(const string& export_dir, SavedModel* saved_model_proto) {
  export_dir);
  }
  -Status FindMetaGraphDef(const SavedModel& saved_model_proto,
  - const std::unordered_set<string>& tags,
  +Status FindMetaGraphDef(const std::unordered_set<string>& tags,
  + SavedModel* saved_model_proto,
  MetaGraphDef* meta_graph_def) {
  LOG(INFO) << "Reading meta graph with tags { " << absl::StrJoin(tags, " ")
  << " }";
  - for (const MetaGraphDef& graph_def : saved_model_proto.meta_graphs()) {
  + for (MetaGraphDef& graph_def : *saved_model_proto->mutable_meta_graphs()) {
  // Get tags from the graph_def.
  std::unordered_set<string> graph_tags;
  for (const string& tag : graph_def.meta_info_def().tags()) {
  @@ -61,7 +61,7 @@ Status FindMetaGraphDef(const SavedModel& saved_model_proto,
  }
  // Match with the set of tags provided.
  if (graph_tags == tags) {
  - *meta_graph_def = graph_def;
  + *meta_graph_def = std::move(graph_def);
  return Status::OK();
  }
  }
  @@ -81,7 +81,8 @@ Status ReadMetaGraphDefFromSavedModel(const string& export_dir,
  MetaGraphDef* const meta_graph_def) {
  SavedModel saved_model_proto;
  TF_RETURN_IF_ERROR(ReadSavedModel(export_dir, &saved_model_proto));
  - TF_RETURN_IF_ERROR(FindMetaGraphDef(saved_model_proto, tags, meta_graph_def));
  + TF_RETURN_IF_ERROR(
  + FindMetaGraphDef(tags, &saved_model_proto, meta_graph_def));
  return Status::OK();
  }
  