Issue #2613878 by edysmp, heddn, Adita, Lord_of_Codes, jian he, chx, miiimooo,...

Issue #2613878 by edysmp, heddn, Adita, Lord_of_Codes, jian he, chx, miiimooo, alexpott, benjy, mikeryan: Use hash for Migration source keys, rather than verbatim values

(cherry picked from commit bd71f241)