Core: Do not use STL container size method to check if container is empty

src/server/scripts/EasternKingdoms/Karazhan/boss_midnight.cpp

@@ -286,7 +286,7 @@ void boss_attumen::boss_attumenAI::UpdateAI(const uint32 diff)
                     target_list.push_back(pTarget);
                 pTarget = NULL;
             }
-            if (target_list.size())
+            if (!target_list.empty())
                 pTarget = *(target_list.begin()+rand()%target_list.size());
 
             DoCast(pTarget, SPELL_BERSERKER_CHARGE);

src/server/scripts/EasternKingdoms/Karazhan/boss_prince_malchezaar.cpp

@@ -312,7 +312,7 @@ public:
             std::list<HostileReference *> t_list = me->getThreatManager().getThreatList();
             std::vector<Unit* > targets;
 
-            if (!t_list.size())
+            if (t_list.empty())
                 return;
 
             //begin + 1, so we don't target the one with the highest threat