Revert "PR14606: debug info imported_module support"

This reverts commit r179836 as it seems to have caused test failures.

llvm-svn: 179840
diff --git a/llvm/test/DebugInfo/X86/objc-fwd-decl.ll b/llvm/test/DebugInfo/X86/objc-fwd-decl.ll
index 3070ff8..1847d2c 100644
--- a/llvm/test/DebugInfo/X86/objc-fwd-decl.ll
+++ b/llvm/test/DebugInfo/X86/objc-fwd-decl.ll
@@ -12,7 +12,7 @@
 !llvm.dbg.cu = !{!0}
 !llvm.module.flags = !{!9, !10, !11, !12}
 
-!0 = metadata !{i32 786449, metadata !13, i32 16, metadata !"clang version 3.1 (trunk 152054 trunk 152094)", i1 false, metadata !"", i32 2, metadata !1, metadata !1, metadata !1, metadata !3,  metadata !3, metadata !""} ; [ DW_TAG_compile_unit ]
+!0 = metadata !{i32 786449, metadata !13, i32 16, metadata !"clang version 3.1 (trunk 152054 trunk 152094)", i1 false, metadata !"", i32 2, metadata !1, metadata !1, metadata !1, metadata !3, metadata !""} ; [ DW_TAG_compile_unit ]
 !1 = metadata !{i32 0}
 !3 = metadata !{metadata !5}
 !5 = metadata !{i32 786484, i32 0, null, metadata !"a", metadata !"a", metadata !"", metadata !6, i32 3, metadata !7, i32 0, i32 1, %0** @a, null} ; [ DW_TAG_variable ]