[PM] Replace the hard invalidate in JumpThreading for LVI with correct

[PM] Replace the hard invalidate in JumpThreading for LVI with correct
invalidation of deleted functions in GlobalDCE.

This was always testing a bug really triggered in GlobalDCE. Right now
we have analyses with asserting value handles into IR. As long as those
remain, when *deleting* an IR unit, we cannot wait for the normal
invalidation scheme to kick in even though it was designed to work
correctly in the face of these kinds of deletions. Instead, the pass
needs to directly handle invalidating the analysis results pointing at
that IR unit.

I've tought the Inliner about this and this patch teaches GlobalDCE.
This will handle the asserting VH case in the existing test as well as
other issues of the same fundamental variety. I've moved the test into
the GlobalDCE directory and added a comment explaining what is going on.

Note that we cannot simply require LVI here because LVI is too lazy.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@292773 91177308-0d34-0410-b5e6-96231b3b80d8