Move a free function from the Frontend library into the Lex library as
part of HeaderSearch. This function just normalizes filenames for use
inside of a synthetic include directive, but it is used in both the
Frontend and Serialization libraries so it needs a common home.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@146227 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed