Bind refactoring: guest_view

Explicitly mark GuestCallback as a RepeatingCallback and use BindRepeating on all callers

BUG=714018
TBR=sky@chromium.org

Change-Id: I5e1d7283b421872291fad9131fb6977d1ba8b3c0
Reviewed-on: https://chromium-review.googlesource.com/970904
Commit-Queue: Mark Pilgrim <pilgrim@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#545061}
13 files changed