don't NPE on 50x's - as per BOTS-170
don't NPE on 50x's - as per BOTS-170

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