message: Simplify DebugString functions
diff: @@ -118,30 +118,19 @@ string DebugString(const nvinfer1::ITensor& tensor) {
  }
  string DebugString(const std::vector<nvinfer1::Dims>& dimvec) {
  - string out = "[";
  - for (auto dims: dimvec) {
  - StrAppend(&out, DebugString(dims));
  - }
  - StrAppend(&out, "]");
  - return out;
  + return absl::StrCat("[",
  + absl::StrJoin(dimvec, ",",
  + [](std::string* out, nvinfer1::Dims in)
  + {out->append(DebugString(in));}),
  + "]");
  }
  string DebugString(const std::vector<TensorShape>& shapes) {
  - string out = "[";
  - for (auto shape: shapes) {
  - StrAppend(&out, shape.DebugString());
  - }
  - StrAppend(&out, "]");
  - return out;
  + return TensorShapeUtils::ShapeListString(shapes);
  }
  string DebugString(const std::vector<PartialTensorShape>& shapes) {
  - string out = "[";
  - for (auto shape: shapes) {
  - StrAppend(&out, shape.DebugString());
  - }
  - StrAppend(&out, "]");
  - return out;
  + return PartialTensorShapeUtils::PartialShapeListString(shapes);
  }
  #endif
  