Detect call type by examining the SDP always rather than just in Firefox as it seems Chrome's behaviour is the odd one out here.

Don't cache isWebRTCSupported because whether webRTC is supported might change part-way through the page's lifecycle if your webrtc support comes from some kind of injected content script (hello OpenWebRTC Sarafi extension)

Swap from using raw m.room.member events for room members to using actual RoomMember objects, so User objects can be tacked on. Update tests.

Skip the tests which test for urlencoding, and add a TODO
in matrixService.

Webclient room data restructure

This works for both live and paginated events. Each 'message' event has
an associated '__room_member' key which points to the state of the sender
at that point in time. Invites have an additional key '__target_room_member'
which point to the state of the invitee at that point in time. This obviates
the need for mapping user_ids to *current* displaynames in the message list,
though this is still required for the user/presence list.