grouping: fix circular-slice equal.
grouping: fix circular-slice equal.

dch/factor,bjourne/factor,slavapestov/factor,sarvex/factor-lang,mrjbq7/factor,nicolas-p/factor,mrjbq7/factor,tgunr/factor,AlexIljin/factor,sarvex/factor-lang,bpollack/factor,mrjbq7/factor,sarvex/factor-lang,bpollack/factor,slavapestov/factor,factor/factor,sarvex/factor-lang,slavapestov/factor,AlexIljin/factor,slavapestov/factor,AlexIljin/factor,bjourne/factor,nicolas-p/factor,nicolas-p/factor,slavapestov/factor,factor/factor,bpollack/factor,tgunr/factor,sarvex/factor-lang,bjourne/factor,dch/factor,factor/factor,AlexIljin/factor,mrjbq7/factor,tgunr/factor,dch/factor,bjourne/factor,factor/factor,sarvex/factor-lang,bjourne/factor,dch/factor,bpollack/factor,nicolas-p/factor,bpollack/factor,factor/factor,bjourne/factor,nicolas-p/factor,nicolas-p/factor,tgunr/factor,factor/factor,AlexIljin/factor,dch/factor,slavapestov/factor,tgunr/factor,dch/factor,AlexIljin/factor,bjourne/factor,bpollack/factor,mrjbq7/factor,tgunr/factor,sarvex/factor-lang,AlexIljin/factor,nicolas-p/factor,slavapestov/factor,mrjbq7/factor,bpollack/factor