Remove ptr::eq() from Cell::swap()

[ChayimFriedman2]

It looks redundant to me, since we use ptr::swap() and not swap_nonoverlapping() so even if they are the same cell it's fine, no?

I think we could also leave the comparison and use swap_nonoverlapping() but I'm less sure about that, since maybe we have a valid way to obtain partially overlapping cells? I can't think of such way, but I am not sure.

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[ChrisDenton]

Is this perhaps an optimization?

I think we could also leave the comparison and use swap_nonoverlapping() but I'm less sure about that, since maybe we have a valid way to obtain partially overlapping cells? I can't think of such way, but I am not sure.

See also #80778