Upon termination of the trust, the trustee shall transfer the unexpended trust property in the following order:

(1) As directed in the instrument;

(2) If the trust was created in a nonresiduary clause in the trustor's will or in a codicil to the trustor's will and the will or codicil does not direct otherwise, under the residuary clause in the trustor's will, which shall be read as though the testator died on the date the trust terminated; and

(3) If no taker is produced by the application of subsection (1) or (2) of this section, to the trustor's heirs under RCW 11.04.015, as it exists at the time of the trust's termination.