refactor an better comment framework lookup code.  This moves it from 
HeaderSearch into DirectoryLookup, as a particular framework lookup is 
specific to the directory we are currently querying.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@45093 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed