Bukkit/CraftBukkit — pull request #730 by pqqqqq (2012-03-17 00:42:22+00:00)
Title: Added check if item is air - Fixes BUKKIT-1201

This checks if the item is air before updating it and checking it in the Item byId list in which it is not apparent.

This fixes the https://bukkit.atlassian.net/browse/BUKKIT-1201 bug where the item would dissapear, but the client would crash due to the unhandled properly packet.