Revert "Fix potential NPE in vanish API. Fixes BUKKIT-1541"

This reverts commit ebf121800bd3161e4af0f6d9229ccb39c31fc278.

If the handle ever becomes null we need to know about it so we can debug it further.

src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java

@@ -591,10 +591,6 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         if (hiddenPlayers.containsKey(player.getName())) return;
         hiddenPlayers.put(player.getName(), player);
 
-        if (getHandle().netServerHandler == null) {
-            return;
-        }
-
         //remove this player from the hidden player's EntityTrackerEntry
         EntityTracker tracker = ((WorldServer) entity.world).tracker;
         EntityPlayer other = ((CraftPlayer) player).getHandle();
@@ -613,10 +609,6 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         if (!hiddenPlayers.containsKey(player.getName())) return;
         hiddenPlayers.remove(player.getName());
 
-        if (getHandle().netServerHandler == null) {
-            return;
-        }
-
         EntityTracker tracker = ((WorldServer) entity.world).tracker;
         EntityPlayer other = ((CraftPlayer) player).getHandle();
         EntityTrackerEntry entry = (EntityTrackerEntry) tracker.trackedEntities.get(other.id);