Revert rC330794 and some dependent tiny bug fixes

Revert rC330794 and some dependent tiny bug fixes

See Richard's humbling feedback here:
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180423/226482.html
http://lists.llvm.org/pipermail/cfe-commits/Week-of-Mon-20180423/226486.html

Wish I'd had the patience to solicit the feedback prior to committing :)

Sorry for the noise guys.

Thank you Richard for being the steward that clang deserves!

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@330888 91177308-0d34-0410-b5e6-96231b3b80d8