Minor fix: don't crash on empty configuration file, consider empty configuration files invalid.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@182290 91177308-0d34-0410-b5e6-96231b3b80d8
ReleaseNotes.rst: typo

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@182294 91177308-0d34-0410-b5e6-96231b3b80d8