Remove the language parameter and variable from the compile unit. We
can get it via the MDNode that's passed in. Save that instead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189291 91177308-0d34-0410-b5e6-96231b3b80d8
Remove duplicate set of CompilationDir.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189292 91177308-0d34-0410-b5e6-96231b3b80d8