Sebastian Graf authored Jun 22, 2021 and Marge Bot committed Jun 27, 2021

Strong loop-breakers never inline, INLINE pragma or not.
Hence they should be treated as if there was no INLINE pragma on them.

Also not doing Cast W/W for INLINE strong loop-breakers will trip up Strictness
W/W, because it treats them as if there was no INLINE pragma. Subsequently,
that will lead to a panic once Strictness W/W will no longer do eta-expansion,
as we discovered while implementing !5814.

I also renamed to `unfoldingInfo` to `realUnfoldingInfo` and redefined
`unfoldingInfo` to zap the unfolding it returns in case of a strong loop-breaker.
Now the naming and semantics is symmetrical to `idUnfolding`/`realIdUnfolding`.

Now there was no more reason for `hasInlineUnfolding` to operate on `Id`,
because the zapping of strong loop-breaker unfoldings moved from `idUnfolding`
to `unfoldingInfo`, so I refactored it to take `IdInfo` and call it both from
the Simplifier and WorkWrap, making it utterly clear that both checks are
equivalent.