Method focusTab

src/material/tabs/tab-group.ts:466–472

* Sets focus to a particular tab. * @param index Index of the tab to be focused.

(index: number)

   * @param index Index of the tab to be focused.
   */
  focusTab(index: number) {
    const header = this._tabHeader;

    if (header) {
      header.focusIndex = index;
    }
  }

  _focusChanged(index: number) {
    this._lastFocusedTabIndex = index;