[beta] Backport: Re-enable len_zero for ranges now that `is_empty` is stable on them#5982

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flip1995 merged 1 commit intorust-lang:betafrom

flip1995:backport

Aug 29, 2020

Commits on Aug 28, 2020

Re-enable len_zero for ranges now that `is_empty` is stable on them

scottmcm
authored and
flip1995
committed