Fixes https://github.com/matrix-org/synapse/issues/3018



Signed-off-by: Travis Ralston <travpc@gmail.com>

Signed-off-by: Travis Ralston <travpc@gmail.com>

Signed-off-by: Travis Ralston <travpc@gmail.com>

(Really) fix tablescan of event_push_actions on purge

commit 278d21b5 added new code to avoid the tablescan, but didn't remove the
old :/

Store push actions in DB staging area instead of context

Don't serialize current state over replication

Don't log errors propogated from send_event

Fix state group storage bug in workers

We needed to move `_count_state_group_hops_txn` to the
StateGroupWorkerStore.

purge_history cleanups

switch back from GIST to GIN indexes

apparently sqlite insists on indexes being named

apparently creating a temporary table commits the transaction. because that's a
useful thing.

event_push_actions doesn't have an index on event_id, so we need to specify
room_id.

... which should speed things up by reducing the amount of data being shuffled
across the connection

Create a worker for event creation

(we don't just remove remote events)

We're up to schema v47 on develop now, so this will have to go in there to have
an effect.

This might cause an error if somebody has already run it in the v46 guise, and
runs it again in the v47 guise, because it will cause a duplicate entry in the
bbackground_updates table. On the other hand, the entry is removed once it is
complete, and it is unlikely that anyone other than matrix.org has run it on
v46. The update itself is harmless to re-run because it deliberately copes with
the index already existing.

Use StateResolutionHandler to resolve state in persist_events

* It's supposed to be purge_local_events, not ..._history
* Fix the doc to have valid json

Allow use of higher versions of saml2

Tell storage providers about new file so they can upload

delete_local_events for purge_room_history