message: [RandomAccessInputStream] Use `tstring::resize_uninitialized()` in `ReadNBytes()`.
  This avoids unnecessarily `memset`ting the bytes that are about to be overwritten.
diff: @@ -35,7 +35,7 @@ Status RandomAccessInputStream::ReadNBytes(int64 bytes_to_read,
  return errors::InvalidArgument("Cannot read negative number of bytes");
  }
  result->clear();
  - result->resize(bytes_to_read);
  + result->resize_uninitialized(bytes_to_read);
  char* result_buffer = &(*result)[0];
  StringPiece data;
  Status s = file_->Read(pos_, bytes_to_read, &data, result_buffer);
  