Method _clearPreviousCache

src/cdk/tree/tree.ts:1173–1177

Clears the maps we use to store parents, level & aria-sets in.

()

  /** Clears the maps we use to store parents, level & aria-sets in. */
  private _clearPreviousCache() {
    this._parents.clear();
    this._levels.clear();
    this._ariaSets.clear();
  }
}

/**