*Try to fix the crash caused by invalid map pointer of player.

--HG--
branch : trunk

src/game/Map.cpp

@@ -2643,14 +2643,11 @@ void InstanceMap::PermBindAllPlayers(Player *player)
 
 void InstanceMap::UnloadAll()
 {
-    if(HavePlayers())
+    while(HavePlayers())
     {
         sLog.outError("InstanceMap::UnloadAll: there are still players in the instance at unload, should not happen!");
-        for(MapRefManager::iterator itr = m_mapRefManager.begin(); itr != m_mapRefManager.end(); ++itr)
-        {
-            Player* plr = itr->getSource();
-            plr->TeleportTo(plr->m_homebindMapId, plr->m_homebindX, plr->m_homebindY, plr->m_homebindZ, plr->GetOrientation());
-        }
+        Player *plr = m_mapRefManager.getFirst()->getSource();
+        plr->TeleportOutOfMap(this);
     }
 
     if(m_resetAfterUnload == true)
@@ -2742,14 +2739,9 @@ void BattleGroundMap::UnloadAll()
 {
     while(HavePlayers())
     {
-        if(Player * plr = m_mapRefManager.getFirst()->getSource())
-        {
-            plr->TeleportTo(plr->GetBattleGroundEntryPoint());
-            // TeleportTo removes the player from this map (if the map exists) -> calls BattleGroundMap::Remove -> invalidates the iterator.
-            // just in case, remove the player from the list explicitly here as well to prevent a possible infinite loop
-            // note that this remove is not needed if the code works well in other places
-            plr->GetMapRef().unlink();
-        }
+        Player *plr = m_mapRefManager.getFirst()->getSource();
+        plr->TeleportTo(plr->GetBattleGroundEntryPoint());
+        plr->TeleportOutOfMap(this);
     }
 
     Map::UnloadAll();

src/game/Player.cpp

@@ -1621,6 +1621,21 @@ void Player::SendTeleportAckMsg()
     GetSession()->SendPacket(&data);
 }
 
+void Player::TeleportOutOfMap(Map *oldMap)
+{
+    if(FindMap() != oldMap)
+        return;
+
+    TeleportTo(m_homebindMapId, m_homebindX, m_homebindY, m_homebindZ, GetOrientation());
+
+    if(FindMap() == oldMap)
+    {
+        sLog.outCrash("Cannot teleport player out of map!");
+        ResetMap();
+        assert(false);
+    }
+}
+
 bool Player::TeleportTo(uint32 mapid, float x, float y, float z, float orientation, uint32 options)
 {
     if(!MapManager::IsValidMapCoord(mapid, x, y, z, orientation))

src/game/Player.h

@@ -900,6 +900,7 @@ class TRINITY_DLL_SPEC Player : public Unit
         void RemoveFromWorld();
 
         bool TeleportTo(uint32 mapid, float x, float y, float z, float orientation, uint32 options = 0);
+        void TeleportOutOfMap(Map *oldMap);
 
         bool TeleportTo(WorldLocation const &loc, uint32 options = 0)
         {