Re-enable iOS transitions test in devicelab (#9097)
Re-enable iOS transitions test in devicelab (#9097)

This reverts commit 326355f0f913c954f92aa74612daa78be22755dd.
cbracken/flutter,Hixie/flutter,flutter/flutter,turnidge/flutter,Hixie/flutter,flutter/flutter,flutter/flutter,Hixie/flutter,flutter/flutter,Hixie/flutter,turnidge/flutter,cbracken/flutter,flutter/flutter,flutter/flutter,turnidge/flutter,tvolkert/flutter,tvolkert/flutter,Hixie/flutter,cbracken/flutter,flutter/flutter,turnidge/flutter,flutter/flutter,tvolkert/flutter,cbracken/flutter,tvolkert/flutter,turnidge/flutter,Hixie/flutter,tvolkert/flutter,cbracken/flutter,flutter/flutter,cbracken/flutter,tvolkert/flutter,cbracken/flutter,tvolkert/flutter,cbracken/flutter,cbracken/flutter,tvolkert/flutter,flutter/flutter,Hixie/flutter,tvolkert/flutter,Hixie/flutter,Hixie/flutter,tvolkert/flutter,Hixie/flutter,cbracken/flutter