Slightly modernize PholioImageQuery

Summary:
Ref T11351. My end goal is to remove applyInitialEffects() from Pholio to clear the way for D19897.

Start with some query modernization.

Test Plan: Browsed Pholio, nothing appeared to have changed.

Reviewers: amckinley

Reviewed By: amckinley

Maniphest Tasks: T11351

Differential Revision: https://secure.phabricator.com/D19910