message: global_heap: remove unused mersenne twister RNG
diff: @@ -46,7 +46,6 @@ public:
  GlobalHeap()
  : _maxObjectSize(SizeMap::ByteSizeForClass(kNumBins - 1)),
  - _prng(internal::seed()),
  _fastPrng(internal::seed(), internal::seed()),
  _lastMesh{std::chrono::high_resolution_clock::now()} {
  }
  @@ -398,7 +397,6 @@ private:
  // always accessed with the mhRWLock exclusively locked
  size_t _miniheapCount{0};
  - mt19937_64 _prng;
  MWC _fastPrng;
  BinnedTracker<MiniHeap> _littleheaps[kNumBins];
  