Fix Phriction feed stories text rendering

Summary: Fixes T3763. All this junk needs some actual fixing at some point, but stop it from fataling.

Test Plan: Used feed.query with view=text. Before this patch, Phriction stories fataled. Now they render reasonably.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Maniphest Tasks: T3763

Differential Revision: https://secure.phabricator.com/D6819