This scans text nodes in the DOM for room notifications and turns
them into pills. Changes the pillification code around a bit so it
works with text nodes. Uses the push processor directly to test
the event against the room notifiation rule so we know whether
this event would actually trigger a room notification (needs to
hook into push at a lower level because otherwise our own room
notifications would not pillify since our own events never
generate notifications).
Requires https://github.com/matrix-org/matrix-js-sdk/pull/565
instead of using the converted matrix.to href. This is undesirable and a better solution would be to fix routing in Riot in general and then change user pills to do something like `/room/../member/@userId`.
This makes sure the selection state is correct when moving the cursor through an entity in the composer but only in rich text mode. https://github.com/vector-im/riot-web/issues/4666 still persists despite this, probably because the text content inserted during a completion in markdown mode has a different length to the text node within the entity.
fixesvector-im/riot-web#4654
Instead of relying on the local avatar/displayname of a user, request the data from the server and update the pill if it shows up.
This required a slight refactor which means we're not doing everything in `render` now. Also I noticed unknown rooms weren't being rendered _at all_! So now you get something that looks like a normal link but with the room alias/ID in it.
This isn't an entirely side-effect-free refactoring:
- the text of the timeline pills is now either the room ID/alias or user ID/ display name of the linked resource (which means that until we do a roundtrip to get user displaynames, mentions for users not in the current room will have their user IDs shown instead of what was in the link body).
- timeline links to rooms without avatars are now rendered as links
- fixed issue that would throw an error whilst rendering (i.e. unusable client) a room link to a room that the client doesn't know about
