Summary: Ref T5655. It is superfluous to include "base" in the name of an abstract base class. Furthermore, it is not done consistently within the code base. Test Plan: Ran `arc unit`. Reviewers: epriestley, #blessed_reviewers Reviewed By: epriestley, #blessed_reviewers Subscribers: epriestley, Korvin Maniphest Tasks: T5655 Differential Revision: https://secure.phabricator.com/D9989