Core/Quests: ported quest flag and visbility update changes from master branch

src/server/game/Spells/SpellEffects.cpp

@@ -4314,7 +4314,7 @@ void Spell::EffectQuestComplete(SpellEffIndex effIndex)
         uint16 logSlot = player->FindQuestSlot(questId);
         if (logSlot < MAX_QUEST_LOG_SIZE)
             player->AreaExploredOrEventHappens(questId);
-        else if (quest->HasFlag(QUEST_FLAGS_TRACKING))  // Check if the quest is used as a serverside flag.
+        else if (quest->HasFlag(QUEST_FLAGS_TRACKING_EVENT)) // Check if the quest is used as a serverside flag.
             player->SetRewardedQuest(questId);          // If so, set status to rewarded without broadcasting it to client.
     }
 }