fix inline comment for new differential fluid view

Summary: we need to render left and right* classes as appropriate, plus colspan for the right

Test Plan: made inline comments and it was no longer borked

Reviewers: vrana, epriestley, chad

Reviewed By: chad

CC: aran, Korvin

Maniphest Tasks: T2005

Differential Revision: https://secure.phabricator.com/D4131