async updateMarkerPositions_(positionUpdates) {
    const filteredPositionUpdates = positionUpdates.filter(
      (positionUpdate) => positionUpdate.workspaceId != this.workspaceId,
    );
    filteredPositionUpdates.forEach((positionUpdate) => {
      const position = positionUpdate.position;
      const node = position.createNode(this.getWorkspace_());
      if (this.getMarker(positionUpdate.workspaceId)) {
        this.getMarker(positionUpdate.workspaceId).setCurNode(node);
      } else {
        this.createMarker_(positionUpdate).setCurNode(node);
      }
    });
  }
Updates curNode on a Marker based on MarkerPosition.
@param {!<Array.<!PositionUpdate>>} positionUpdates The PositionUpdates which
contain the new MarkerPositions.
@private