bring room name calculation in line with summary spec, while maintaining some backwards compatibility
bring room name calculation in line with summary spec, while maintaining some backwards compatibility

matrix-org/matrix-js-sdk,krombel/matrix-js-sdk,krombel/matrix-js-sdk,matrix-org/matrix-js-sdk,matrix-org/matrix-js-sdk,krombel/matrix-js-sdk,matrix-org/matrix-js-sdk