message: Added safety agains non existing fVertex
diff: @@ -659,10 +659,10 @@ Bool_t AliAnalysisTaskTOFqaID::IsEventSelected(AliESDEvent* event)
  return kFALSE;
  }
  fVertex = (AliESDVertex*)event->GetPrimaryVertexTracks();
  - if (fVertex->GetNContributors() < 1) {
  + if (!fVertex || fVertex->GetNContributors() < 1) {
  // SPD vertex
  fVertex = (AliESDVertex*)event->GetPrimaryVertexSPD();
  - if (fVertex->GetNContributors() < 1)
  + if (!fVertex || fVertex->GetNContributors() < 1)
  fVertex = 0x0;
  }
  if (!fVertex)
  