Core/Corpses: Fixed a possible crash adding bones to grid

Closes #15808

(cherry picked from commit ec1583df67605b7253a34dc5f153cdad5b16969e)

src/server/game/Maps/Map.cpp

@@ -303,19 +303,19 @@ template<>
 void Map::AddToGrid(Corpse* obj, Cell const& cell)
 {
     NGridType* grid = getNGrid(cell.GridX(), cell.GridY());
-    if (obj->IsWorldObject())
+    // Corpses are a special object type - they can be added to grid via a call to AddToMap
+    // or loaded through ObjectGridLoader.
+    // Both corpses loaded from database and these freshly generated by Player::CreateCoprse are added to _corpsesByCell
+    // ObjectGridLoader loads all corpses from _corpsesByCell even if they were already added to grid before it was loaded
+    // so we need to explicitly check it here (Map::AddToGrid is only called from Player::BuildPlayerRepop, not from ObjectGridLoader)
+    // to avoid failing an assertion in GridObject::AddToGrid
+    if (grid->isGridObjectDataLoaded())
     {
-        // Corpses are a special object type - they can be added to grid via a call to AddToMap
-        // or loaded through ObjectGridLoader.
-        // Both corpses loaded from database and these freshly generated by Player::CreateCoprse are added to _corpsesByCell
-        // ObjectGridLoader loads all corpses from _corpsesByCell even if they were already added to grid before it was loaded
-        // so we need to explicitly check it here (Map::AddToGrid is only called from Player::BuildPlayerRepop, not from ObjectGridLoader)
-        // to avoid failing an assertion in GridObject::AddToGrid
-        if (grid->isGridObjectDataLoaded())
+        if (obj->IsWorldObject())
             grid->GetGridType(cell.CellX(), cell.CellY()).AddWorldObject(obj);
+        else
+            grid->GetGridType(cell.CellX(), cell.CellY()).AddGridObject(obj);
     }
-    else
-        grid->GetGridType(cell.CellX(), cell.CellY()).AddGridObject(obj); // bones. nothing special here
 }
 
 template<class T>