Clairvoyance removal from Twisted Treeline

From the patch notes it said it was being removed from Summoner's Rift, but on the spells page in the client it is only listed as being available in the Tutorial and Dominion. I understand it was a stinker on SR when there are other vision options available, but it was very useful (personally) on Twisted Treeline where vision options are sparse. Was this an oversight? Is this something that can be restored? I promised myself I wouldn't make a "rito plz" post, but here I am. For the sake of my dignity and a useful summoner spell, bring back Clairvoyance to the treeline. Thank you.