fix(SDPDiffer): throw for illegal args
fix(SDPDiffer): throw for illegal args

Will crash the code early in case one of the value is undefined (it will
crash later anyway, but makes it harder to guess).

jitsi/lib-jitsi-meet,jiyeyuran/lib-jitsi-meet,nevermind-corp/ljm,adambowles/lib-jitsi-meet,adambowles/lib-jitsi-meet,damencho/lib-jitsi-meet,jitsi/lib-jitsi-meet