Add a null-correcntess test for strict takeWhileEnd (gh-184)
Add a null-correcntess test for strict takeWhileEnd (gh-184)

(cherry picked from commit ddac7b55bfb9c86663ee6485df0fc4372954b38a)

text-utf8/text,text-utf8/text,text-utf8/text,text-utf8/text