message: Rip hover support out of the RoomTile component
  It's all handled by CSS and this literally does nothing but spam renders.
diff: @@ -67,7 +67,6 @@ interface IProps {
  type PartialDOMRect = Pick<DOMRect, "left" | "bottom">;
  interface IState {
  - hover: boolean;
  notificationState: NotificationState;
  selected: boolean;
  notificationsMenuPosition: PartialDOMRect;
  @@ -119,7 +118,6 @@ export default class RoomTile extends React.Component<IProps, IState> {
  super(props);
  this.state = {
  - hover: false,
  notificationState: RoomNotificationStateStore.instance.getRoomState(this.props.room),
  selected: ActiveRoomObserver.activeRoomId === this.props.room.roomId,
  notificationsMenuPosition: null,
  @@ -206,14 +204,6 @@ export default class RoomTile extends React.Component<IProps, IState> {
  });
  };
  - private onTileMouseEnter = () => {
  - this.setState({hover: true});
  - };
  -
  - private onTileMouseLeave = () => {
  - this.setState({hover: false});
  - };
  -
  private onTileClick = (ev: React.KeyboardEvent) => {
  ev.preventDefault();
  ev.stopPropagation();
  @@ -592,8 +582,6 @@ export default class RoomTile extends React.Component<IProps, IState> {
  tabIndex={isActive ? 0 : -1}
  inputRef={ref}
  className={classes}
  - onMouseEnter={this.onTileMouseEnter}
  - onMouseLeave={this.onTileMouseLeave}
  onClick={this.onTileClick}
  onContextMenu={this.onContextMenu}
  role="treeitem"
  