message: MELS: either expanded or summary, not both
  Fixes vector-im/riot-web#3097
diff: @@ -108,7 +108,7 @@ module.exports = React.createClass({
  }
  return (
  - <span>
  + <span className="mx_TextualEvent mx_MemberEventListSummary_summary">
  {summaries.join(", ")}
  </span>
  );
  @@ -264,7 +264,7 @@ module.exports = React.createClass({
  );
  });
  return (
  - <span>
  + <span className="mx_MemberEventListSummary_avatars">
  {avatars}
  </span>
  );
  @@ -397,31 +397,28 @@ module.exports = React.createClass({
  (seq1, seq2) => aggregate.indices[seq1] > aggregate.indices[seq2]
  );
  - const avatars = this._renderAvatars(avatarMembers);
  - const summary = this._renderSummary(aggregate.names, orderedTransitionSequences);
  - const toggleButton = (
  - <a className="mx_MemberEventListSummary_toggle" onClick={this._toggleSummary}>
  - {expanded ? 'collapse' : 'expand'}
  - </a>
  - );
  -
  - const summaryContainer = (
  + let summaryContainer = null;
  + if (!expanded) {
  + summaryContainer = (
  <div className="mx_EventTile_line">
  <div className="mx_EventTile_info">
  - <span className="mx_MemberEventListSummary_avatars">
  - {avatars}
  - </span>
  - <span className="mx_TextualEvent mx_MemberEventListSummary_summary">
  - {summary}
  - </span>&nbsp;
  - {toggleButton}
  + {this._renderAvatars(avatarMembers)}
  + {this._renderSummary(aggregate.names, orderedTransitionSequences)}
  </div>
  </div>
  );
  + }
  + const toggleButton = (
  + <div className={"mx_MemberEventListSummary_toggle"} onClick={this._toggleSummary}>
  + {expanded ? 'collapse' : 'expand'}
  + </div>
  + );
  return (
  <div className="mx_MemberEventListSummary">
  + {toggleButton}
  {summaryContainer}
  + {expanded ? <div className="mx_MemberEventListSummary_line">&nbsp;</div> : null}
  {expandedEvents}
  </div>
  );
  