_setSubviewsNeedDisplay() {
    this._subviewsNeedDisplay = true;

    if (this.superview) {
      this.superview._setSubviewsNeedDisplay();
    }
  }
Informs superview that it has subviews that need to be drawn.

Upward propagating; once called, all superviews of this view should also
have `subviewsNeedDisplay` = true.

@private