Fix migration error to AR as search returns instance

issue3470
review1551002
(transplanted from 735e30aa9962bab183965c09bb05c7477caa555c)

--HG--
extra : transplant_source : s%5E0%AA%99b%BA%B1%83%96%5C%09%BB%05%C7G%7C%AAU%5C
percent_complete is required so set 0 as default

issue3470
review1541002
(transplanted from b111827178f3cb41354b782b6aa62090ffb745f0)

--HG--
extra : transplant_source : %B1%11%82qx%F3%CBA5Kx%2Bj%A6%20%90%FF%B7E%F0
Fix typo _table from AR migration

issue3470
review1521003
(transplanted from 1c08aba4f7826c6203836926020cd7c02c5021a2)

--HG--
extra : transplant_source : %1C%08%AB%A4%F7%82lb%03%83i%26%02%0C%D7%C0%2CP%21%A2