message: Remove row exists checks.
diff: @@ -838,17 +838,14 @@ export class Output extends events.EventEmitter {
  }
  deleteRight(n: number) {
  - if (this.storage.get(this.cursorRowIndex)) {
  this.storage = this.storage.update(
  this.cursorRowIndex,
  List<Char>(),
  (row: List<Char>) => row.splice(this.cursorColumnIndex, n).toList(),
  );
  }
  - }
  insertSpaceRight(n: number) {
  - if (this.storage.get(this.cursorRowIndex)) {
  let nSpace = "";
  for (let i = 0; i < n; i++) { nSpace += " "; }
  this.storage = this.storage.update(
  @@ -857,10 +854,8 @@ export class Output extends events.EventEmitter {
  (row: List<Char>) => row.splice(this.cursorColumnIndex, 0, nSpace).toList(),
  );
  }
  - }
  eraseRight(n: number) {
  - if (this.storage.get(this.cursorRowIndex)) {
  this.storage = this.storage.update(
  this.cursorRowIndex,
  List<Char>(),
  @@ -869,7 +864,6 @@ export class Output extends events.EventEmitter {
  .toList(),
  );
  }
  - }
  clearRow() {
  this.storage = this.storage.set(this.cursorRowIndex, this.emptyLine);
  