*Use map pointer of killed creature instead of player pointer to prevent crash in case killer is not in world.

--HG--
branch : trunk

src/game/Formulas.h

@@ -117,7 +117,7 @@ namespace Trinity
                 (((Creature*)u)->GetCreatureInfo()->flags_extra & CREATURE_FLAG_EXTRA_NO_XP_AT_KILL) ))
                 return 0;
 
-            uint32 xp_gain= BaseGain(pl->getLevel(), u->getLevel(), GetContentLevelsForMapAndZone(pl->GetMapId(),pl->GetZoneId()));
+            uint32 xp_gain= BaseGain(pl->getLevel(), u->getLevel(), GetContentLevelsForMapAndZone(u->GetMapId(),u->GetZoneId()));
             if( xp_gain == 0 )
                 return 0;
 

src/game/Unit.cpp

@@ -13668,6 +13668,7 @@ void Unit::SetToNotify()
 
 void Unit::Kill(Unit *pVictim, bool durabilityLoss)
 {
+    assert(pVictim->IsInWorld() && pVictim->FindMap());
     // Prevent killing unit twice (and giving reward from kill twice)
     if (!pVictim->GetHealth())
         return;