getCacheKey( force = false ) {

		force = force || this.version !== this._cacheKeyVersion;

		if ( force === true || this._cacheKey === null ) {

			this._cacheKey = hash$1( getCacheKey$1( this, force ), this.customCacheKey() );
			this._cacheKeyVersion = this.version;

		}

		return this._cacheKey;

	}
Returns the cache key for this node.

@param {boolean} [force=false] - When set to `true`, a recomputation of the cache key is forced.
@return {number} The cache key of the node.