message: specify alternate history storage key to prevent conflicts with draft
diff: @@ -337,7 +337,7 @@ export default class MessageComposerInput extends React.Component {
  componentDidMount() {
  this.dispatcherRef = dis.register(this.onAction);
  - this.historyManager = new ComposerHistoryManager(this.props.room.roomId);
  + this.historyManager = new ComposerHistoryManager(this.props.room.roomId, 'mx_slate_composer_history_');
  }
  componentWillUnmount() {
  