message: MemberPresenceAvatar: fix null references
  avoid assuming that `member` has a `user`
diff: @@ -44,8 +44,15 @@ module.exports = React.createClass({
  },
  getInitialState: function() {
  - const presenceState = this.props.member.user.presence;
  - const presenceMessage = this.props.member.user.presenceStatusMsg;
  + let presenceState = null;
  + let presenceMessage = null;
  +
  + // RoomMembers do not necessarily have a user.
  + if (this.props.member.user) {
  + presenceState = this.props.member.user.presence;
  + presenceMessage = this.props.member.user.presenceStatusMsg;
  + }
  +
  return {
  status: presenceState,
  message: presenceMessage,
  @@ -109,6 +116,8 @@ module.exports = React.createClass({
  });
  e.stopPropagation();
  +
  + // XXX NB the following assumes that user is non-null, which is not valid
  // const presenceState = this.props.member.user.presence;
  // const presenceLastActiveAgo = this.props.member.user.lastActiveAgo;
  // const presenceLastTs = this.props.member.user.lastPresenceTs;
  