Set viewer for all handles loaded in controllers

Summary:
I've replaced all id(new PhabricatorObjectHandleData(...))->loadHandles() by $this->loadViewerHandles(...).
Lint caught one usage in a static method.

Test Plan: Displayed revision with sporadic author.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D3432