disconnectRoot(root) {
    this.roots.delete(root);
    // Pause the mutation observer to stop observing `root`.
    this.pauseObserving();

    if (this.roots.size === 0) {
      this.mutationObserver = null;
      if (this.windowElement && this.pendingrAF) {
        this.windowElement.cancelAnimationFrame(this.pendingrAF);
      }
      this.windowElement = null;
      this.pendingrAF = null;
      this.pendingElements.clear();
      return true;
    }

    // Resume observing all other roots.
    this.resumeObserving();
    return false;
  }
Remove `root` from the list of roots managed by this `DOMLocalization`.

Additionally, if this `DOMLocalization` has an observer, stop observing
`root`.

Returns `true` if the root was the last one managed by this
`DOMLocalization`.

@param   {Element} root - Root to disconnect.
@returns {boolean}