Mark room versions 7, 8, and 9 as safe (#2318)

* Mark room versions 7, 8, and 9 as safe

Workaround for element-hq/element-web#20166 element-hq/element-web#11820

* Update KNOWN_SAFE_ROOM_VERSION to room version 9

Author: aaronraimist

src/models/room.ts

@@ -55,8 +55,8 @@ import { IStateEventWithRoomId } from "../@types/search";
 // room versions which are considered okay for people to run without being asked
 // to upgrade (ie: "stable"). Eventually, we should remove these when all homeservers
 // return an m.room_versions capability.
-const KNOWN_SAFE_ROOM_VERSION = '6';
-const SAFE_ROOM_VERSIONS = ['1', '2', '3', '4', '5', '6'];
+const KNOWN_SAFE_ROOM_VERSION = '9';
+const SAFE_ROOM_VERSIONS = ['1', '2', '3', '4', '5', '6', '7', '8', '9'];
 
 function synthesizeReceipt(userId: string, event: MatrixEvent, receiptType: string): MatrixEvent {
     // console.log("synthesizing receipt for "+event.getId());