_onfocusout() {
      if (this._isFocusing()) {
        this._preventFocusOut();
        return;
      }
      this._setAffectedValue(undefined);
      this._startValueInitial = undefined;
      this._endValueInitial = undefined;
      if (this.showTooltip) {
        this._tooltipVisibility = _SliderBase.default.TOOLTIP_VISIBILITY.HIDDEN;
      }
    }
Handles focus out event of the focusable components inner elements.
Prevent focusout when the focus is getting initially set within the slider before the
slider customElement itself is finished focusing.

Prevents the focus from leaving the Range Slider when the focus is managed between
its inner elements in result of user interactions.

Resets the stored Range Slider's initial values saved when it was first focused

@private