Much of this transformation has been done automatically:
* add expect import to each file
* replace `not.to` with `toNot`
* replace `to[Not]Be{Undefined,Null}` with equivalents
* replace `jasmine.createSpy(...)` with `except.createSpy`, and `andCallFake`
with `andCall`
Also:
* replace `jasmine.createSpyObj` with manual alternatives
* replace `jasmine.Clock` with `lolex`
Remove some we don't care about. Set some other ones we do care
about but don't currently adhere to to warn. Set the max warnings
threshold to the current number of warnings, so we don't introduce
more of them. Fix a bunch of legit lint errors and add exceptions
to various places in the test code that does funny things with
'this'.
Removing the last event in an EventTimeline (as we might, for instance, if it
was a local echo in an empty timeline) got us into a state where the baseIndex
would increment when adding events to the end of the timeline, causing much
confusion.
This provides optional support for fetching old events via the /context API,
and paginating backwards and forwards from them, eventually merging into the
live timeline.
To support it, events are now stored in an EventTimeline, rather than directly
in an array in the Room; the old names are maintained as references for
compatibility.
The feature has to be enabled explicitly, otherwise it would be impossible for
existing clients to back-paginate to the old events after a gappy /sync.
Still TODO here:
* An object which provides a window into the timelines to make them possible to
use. This will be a separate PR.
* Rewrite the 'EventContext' used by the searchRoomEvents API in terms of an
EventTimeline - it is essentially a subset.
