Client crash when sending two objective-creation packets with the same name

I fully realize this may be a silly bug report; a crash like this is likely fully normal for a development snapshot (and this one in particular even useful while debugging the scoreboard). Making sure it doesn't slip through to final release regardless.

If you send two scoreboard objective-creation packets to the client with the same objective names, the game will crash with an IllegalArgumentException referencing the duplicate objective

Quick edit here: The game also crashes if an objective-deletion packet with a name unknown to the client is received, however the game does not crash if you send a scoreboard display packet with a name unknown to the client.