Make DebugLoc independent of DwarfWriter.

-Replace DebugLocTuple's Source ID with CompileUnit's GlobalVariable*
-Remove DwarfWriter::getOrCreateSourceID
-Make necessary changes for the above (fix callsites, etc.)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70520 91177308-0d34-0410-b5e6-96231b3b80d8
12 files changed