Fix an issue where inlines could be duplicated in the client list
Instead, when rebuilding, unconditionally discard the old list.
- Added inline comments to a file in Differential.
- Marked some done.
- Scrolled so the inline comment header was visible, saw "X / Y Comments" button in header.
- Clicked "Show 20 more lines" on the changeset with inlines (or toggle "View Unified" / "View Side-by-Side", or other interactions likely work too).
- Before: saw "X / Y" change improperly (because inlines in that file were double-counted).
- After: saw stable count.
- Grepped for "differential-inline-comment-refresh", got no hits, concluded this event has no listeners.
Maniphest Tasks: T13559
Differential Revision: https://secure.phabricator.com/D21642