MSVC: A wide string literal from L#macro_arg in a macro
Clang should form a wide string literal from L#macro_arg in a function-like macro in -fms-compatibility mode.
Fix for http://llvm.org/PR9984.
Differential Revision: http://reviews.llvm.org/D6604


git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@224228 91177308-0d34-0410-b5e6-96231b3b80d8