message: Cell: fixed ts errors
diff: @@ -70,7 +70,7 @@ class Cell extends Component<CellProps, CellState> {
  get document() {return this.context.document || document;}
  - onRemoveActivateClick = (e: MouseEvent) => {
  + private readonly onRemoveActivateClick = (e: MouseEvent) => {
  e.nativeEvent.stopPropagation();
  e.preventDefault();
  this.setState({ isRemoveActivated: true });
  @@ -180,7 +180,7 @@ class Cell extends Component<CellProps, CellState> {
  delete this.dragDirection;
  };
  - onDragClick = (e: MouseEvent) => {
  + private readonly onDragClick = (e: MouseEvent) => {
  e.nativeEvent.stopPropagation();
  e.preventDefault();
  };
  