Method _coerceValue

src/cdk/listbox/listbox.ts:1035–1037

* Coerces a value into an array representing a listbox selection. * @param value The value to coerce * @return An array

(value: readonly T[])

   * @return An array
   */
  private _coerceValue(value: readonly T[]) {
    return value == null ? [] : coerceArray(value);
  }

  /**
   * Get the sublist of values that do not represent valid option values in this listbox.