Fixed crash on iOS prior 7.
Fixed crash on iOS prior 7.

soffes/SAMKeychain,money-alex2006hw/sskeychain,cnbin/sskeychain,dachaoisme/sskeychain,Pointwelve/KeychainKit,jiqiuyucool/sskeychain,Hidebush/sskeychain,gabriel/sskeychain,SuPair/sskeychain,Eveian/sskeychain,jflinter/sskeychain,meganz/sskeychain,lgauthier/sskeychain,soffes/SAMKeychain,HarrisLee/sskeychain,zhaoguohui/sskeychain,iandd0824/sskeychain,wpstarnice/sskeychain,maximmalygin/sskeychain,jkhowland/sskeychain,sdonly/sskeychain,azplanlos/sskeychain,FelixYin66/sskeychain,meganz/sskeychain,liufeigit/sskeychain,jerrykrinock/sskeychain,rhodgkins/sskeychain,soffes/sskeychain,chanelten/sskeychain,Eugene-Gubin/sskeychain,ShowerLi1991/sskeychain,soffes/sskeychain,jaredsinclair/sskeychain