DebugInfo: Use the comp_dir of the referencing type units when building debug_line.dwo

This isn't a complete fix - it falls back to non-comp_dir when multiple
compile units are in play. Adding a map of comp_dir to table is part of
the more general solution, but I gave up (in the short term) when I
realized I'd also have to calculate the size of each type unit so as to
produce correct DW_AT_stmt_list attributes.

llvm-svn: 204202
diff --git a/llvm/test/DebugInfo/X86/generate-odr-hash.ll b/llvm/test/DebugInfo/X86/generate-odr-hash.ll
index 9770163..add1e74 100644
--- a/llvm/test/DebugInfo/X86/generate-odr-hash.ll
+++ b/llvm/test/DebugInfo/X86/generate-odr-hash.ll
@@ -143,6 +143,7 @@
 ; FISSION: Line table prologue
 ; FISSION: opcode_base: 1
 ; FISSION-NOT: standard_opcode_lengths
+; FISSION-NOT: include_directories
 ; FISSION-NOT: file_names[
 ; FISSION: file_names{{.*}} bar.h
 ; FISSION: file_names{{.*}} bar.cpp