[beta] Another round of backports#50182

Merged

bors merged 7 commits intorust-lang:betafrom

alexcrichton:beta-next

Apr 23, 2018

Commits on Apr 22, 2018

smaller PR just to fix #50002

ExpHP
authored and
alexcrichton
committed
fix my unit test that was horrendously wrong

ExpHP
authored and
alexcrichton
committed
Revert stabilization of `feature(never_type)`.

pnkfelix
authored and
alexcrichton
committed
Bring back old fallback semantics: Without feature(never_type), fallback to `()`, not `!`.

pnkfelix
authored and
alexcrichton
committed
Revert "Stabilize the TryFrom and TryInto traits"

pnkfelix
authored and
alexcrichton
committed
Add back missing `#![feature(never_type)]`s

kennytm
authored and
alexcrichton
committed

Commits on Apr 23, 2018

TryFrom destabilization fixups
alexcrichton
committed