Add trace logging to figure out which component is causing weird events

For element-hq/element-web#11120

src/components/views/rooms/EventTile.js

@@ -578,6 +578,7 @@ export default createReactClass({
             console.error("EventTile attempted to get relations for an event without an ID");
             // Use event's special `toJSON` method to log key data.
             console.log(JSON.stringify(this.props.mxEvent, null, 4));
+            console.trace("Stacktrace for https://github.com/vector-im/riot-web/issues/11120");
         }
         return this.props.getRelationsForEvent(eventId, "m.annotation", "m.reaction");
     },