Any trust heretofore or hereafter created for the purposes and of the type enumerated in RCW 49.64.020, whether in real or personal property or in real and personal property, may continue for such time as may be necessary to accomplish the purposes of the trust and shall not be invalid as violating any statute or rule of law against perpetuities, or against accumulations of earnings, or concerning the suspension of the power of alienation of the title to property, or otherwise limiting the duration of trusts.