message: EventIndex: Don't index key verification events.
  Since cross-signing is a thing key verification events have become part
  of the timeline and room history.
  Those events are m.room.message events for backwards compatibility, so
  clients that don't support key verification in the timeline print out a
  fall-back message.
diff: @@ -240,6 +240,36 @@ export default class EventIndex extends EventEmitter {
  this.crawlerCheckpoints.push(backwardsCheckpoint);
  }
  + /**
  + * Check if an event should be added to the event index.
  + *
  + * Most notably we filter events for which decryption failed, are redacted
  + * or aren't of a type that we know how to index.
  + *
  + * @param {MatrixEvent} ev The event that should checked.
  + */
  + isValidEvent(ev) {
  + const validEventType = ([
  + "m.room.message",
  + "m.room.name",
  + "m.room.topic",
  + ].indexOf(ev.getType()) >= 0
  + && !ev.isRedacted() && !ev.isDecryptionFailure()
  + );
  +
  + let validMsgType = true;
  +
  + if (ev.getType() === "m.room.message" && !ev.isRedacted()) {
  + // Expand this if there are more invalid msgtypes.
  + const msgtype = ev.getContent().msgtype;
  +
  + if (!msgtype) validMsgType = false;
  + else validMsgType = !msgtype.startsWith("m.key.verification");
  + }
  +
  + return validEventType && validMsgType;
  + }
  +
  /**
  * Queue up live events to be added to the event index.
  *
  @@ -248,10 +278,7 @@ export default class EventIndex extends EventEmitter {
  async addLiveEventToIndex(ev) {
  const indexManager = PlatformPeg.get().getEventIndexingManager();
  - if (["m.room.message", "m.room.name", "m.room.topic"]
  - .indexOf(ev.getType()) == -1) {
  - return;
  - }
  + if (!this.isValidEvent(ev)) return;
  const jsonEvent = ev.toJSON();
  const e = ev.isEncrypted() ? jsonEvent.decrypted : jsonEvent;
  @@ -407,22 +434,11 @@ export default class EventIndex extends EventEmitter {
  // Let us wait for all the events to get decrypted.
  await Promise.all(decryptionPromises);
  - // We filter out events for which decryption failed, are redacted
  - // or aren't of a type that we know how to index.
  - const isValidEvent = (value) => {
  - return ([
  - "m.room.message",
  - "m.room.name",
  - "m.room.topic",
  - ].indexOf(value.getType()) >= 0
  - && !value.isRedacted() && !value.isDecryptionFailure()
  - );
  - };
  // TODO if there are no events at this point we're missing a lot
  // decryption keys, do we want to retry this checkpoint at a later
  // stage?
  - const filteredEvents = matrixEvents.filter(isValidEvent);
  + const filteredEvents = matrixEvents.filter(this.isValidEvent);
  // Let us convert the events back into a format that EventIndex can
  // consume.
  