[cfe-dev] [Preprocessor] MSVC Preprocessor compatibility fixes

[Keane, Erich via cfe-dev]

Hi all, I've prepared a number of fixes to the preprocessor in the name of MSVC compatibility!

https://reviews.llvm.org/D32046
https://reviews.llvm.org/D32049
https://reviews.llvm.org/D32050
https://reviews.llvm.org/D32051
https://reviews.llvm.org/D32052

Since Richard Smith is the only one who has any chance of being the code owner here, and because Reid is our MSVC compatibility Czar, I added them to the review.  However, if anyone knows of anyone with sufficient knowledge of the preprocessor, I'd appreciate it if you could add them to the review as well!

Thanks all,
Erich