In Drydock log views, respect newlines

Summary: Depends on D19070. Ref T13073. Some messages contain an interesting story or a clever anecdote. Respect newlines during rendering to preserve authorial intent.

Test Plan:
Viewed a message with linebreaks and could still read it.

{F5427754}

Subscribers: PHID-OPKG-gm6ozazyms6q6i22gyam

Maniphest Tasks: T13073

Differential Revision: https://secure.phabricator.com/D19071