Use PhutilClassMapQuery
Use PhutilClassMapQuery

Summary: Use `PhutilClassMapQuery` where appropriate.

Test Plan: Not quite sure.

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D13427

julkiewicz/libphutil,julkiewicz/libphutil,julkiewicz/libphutil