get manager() {
    if (this._manager) return this._manager;

    throw new ManagerError(
      'Component',
      `ModuleManager is not used in this component. 'manager' parameter should be set as 'true'`,
      this
    );
  }
Returns the `ModuleManager` used for this component.
@member {ModuleManager} module:core.Component#manager
@throws {ManagerError}