Adding test cases in a separate commit to make it easier to review how
the test results change.
As expected, in every case, no notifications are generated right now.
Bug: T285528
Change-Id: I25308754112c521d2db8c54ef0c82373456d9e31
The user interface only allows you to subscribe to level 2 headings.
But we would generate events for whatever heading was the closest,
If it was e.g. level 3, no one would receive that notification.
Now we generate events for the closest level 2 heading, or we don't
generate the event at all if there isn't one (if the only headings are
of level 3 and below, or level 1, or if the comment is added before
the first heading on the page).
Bug: T286736
Change-Id: Iae99853070e353ab81c9cc29ef1d53c877adfc66
