PVS-Studio warning V636 for V8

unsigned total_size_;
double source_size_in_kb =
  static_cast<double>(source_size_) / 1024;

void HStatistics::Print() {
  ....
  double normalized_size_in_kb = source_size_in_kb > 0
      ? total_size_ / 1024 / source_size_in_kb
      : 0;
  PrintF("%32s %8.3f ms           %7.3f kB allocated\n",
         "Average per kB source",
         normalized_time, normalized_size_in_kb);
}

This suspicious code was found in V8 project by PVS-Studio static code analyzer.
Warning message is:
V636 The 'total_size_ / 1024' expression was implicitly casted from 'int' type to 'double' type. Consider utilizing an explicit type cast to avoid the loss of a fractional part. An example: double A = (double)(X) / Y;. hydrogen.cc 11023

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