setClassName_(element, fullscreen) {
    if (fullscreen) {
      element.classList.remove(...this.inactiveClassName_);
      element.classList.add(...this.activeClassName_);
    } else {
      element.classList.remove(...this.activeClassName_);
      element.classList.add(...this.inactiveClassName_);
    }
  }
@param {HTMLElement} element Target element
@param {boolean} fullscreen True if fullscreen class name should be active
@private