R1:6ed02e6ee8fb

Restore "Reply" action to Differential inline comments

Summary: Minor issue from D4117, user doesn't get passed down so inline comments are missing their "reply" link.

Test Plan: Looked at Differential, saw reply link.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Differential Revision: https://secure.phabricator.com/D4145