message: AliMCSpectraWeights: IsPhysicalPrimary from AliMCEvent instead of AliStack
diff: @@ -1099,15 +1099,9 @@ void AliMCSpectraWeights::FillMCSpectra(AliMCEvent* mcEvent) {
  AliMCSpectraWeights::CountEventMult();
  }
  - AliStack* MCStack = fMCEvent->Stack();
  - if (!MCStack) {
  - printf("AliMCSpectraWeights::ERROR: fMCStack not available\n");
  - return;
  - }
  -
  bool const ispPbCollision = fstCollisionSystem.find("ppb")!=std::string::npos;
  - for (int iParticle = 0; iParticle < MCStack->GetNtrack(); ++iParticle) {
  + for (int iParticle = 0; iParticle < fMCEvent->GetNumberOfTracks(); ++iParticle) {
  TParticle* mcGenParticle = MCStack->Particle(iParticle);
  if (!mcGenParticle) {
  printf(
  @@ -1116,7 +1110,7 @@ void AliMCSpectraWeights::FillMCSpectra(AliMCEvent* mcEvent) {
  }
  if (!mcGenParticle->GetPDG())
  continue;
  - if (!MCStack->IsPhysicalPrimary(iParticle))
  + if (!fMCEvent->IsPhysicalPrimary(iParticle))
  continue;
  if (TMath::Abs(mcGenParticle->GetPDG()->Charge()) < 0.01 && TMath::Abs(mcGenParticle->GetPdgCode()!=3122))
  continue;
  