Revert r206565 (and r206566 which updated tests).

This commit was attributed to a different person from the person who
posted the patch to the list, and the person who posted it the list
claimed when they did that they were not the author, but that the author
was yet a third person. I don't know what is going on here, but
reverting until the attribution is clear and the author has explicitly
contributed the patch.

Also, the review hasn't really involved any of the MC maintainers and
that seems questionable too.

llvm-svn: 206576