message: Remove unused ThreepidMember class for now
  It's going to be used for future work in this area, but for this particular PR it isn't needed.
diff: @@ -84,35 +84,6 @@ class DirectoryMember extends Member {
  }
  }
  -class ThreepidMember extends Member {
  - _id: string;
  -
  - constructor(id: string) {
  - super();
  - this._id = id;
  - }
  -
  - // This is a getter that would be falsey on all other implementations. Until we have
  - // better type support in the react-sdk we can use this trick to determine the kind
  - // of 3PID we're dealing with, if any.
  - get isEmail(): boolean {
  - return this._id.includes('@');
  - }
  -
  - // These next class members are for the Member interface
  - get name(): string {
  - return this._id;
  - }
  -
  - get userId(): string {
  - return this._id;
  - }
  -
  - getMxcAvatarUrl(): string {
  - return null;
  - }
  -}
  -
  class DMUserTile extends React.PureComponent {
  static propTypes = {
  member: PropTypes.object.isRequired, // Should be a Member (see interface above)
  