Remove unused "isMain" field from DICompileUnit

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176910 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/DebugInfo/2009-11-10-CurrentFn.ll b/test/DebugInfo/2009-11-10-CurrentFn.ll
index 0a23a0c..c196305 100644
--- a/test/DebugInfo/2009-11-10-CurrentFn.ll
+++ b/test/DebugInfo/2009-11-10-CurrentFn.ll
@@ -12,7 +12,7 @@
 
 !llvm.dbg.cu = !{!0}
 
-!0 = metadata !{i32 720913, i32 0, i32 12, metadata !"cf.c", metadata !"/private/tmp", metadata !"clang version 3.0 (trunk 139632)", i1 true, i1 true, metadata !"", i32 0, metadata !1, metadata !1, metadata !3, metadata !1, metadata !""} ; [ DW_TAG_compile_unit ]
+!0 = metadata !{i32 720913, i32 0, i32 12, metadata !"cf.c", metadata !"/private/tmp", metadata !"clang version 3.0 (trunk 139632)", i1 true, metadata !"", i32 0, metadata !1, metadata !1, metadata !3, metadata !1, metadata !""} ; [ DW_TAG_compile_unit ]
 !1 = metadata !{i32 0}
 !3 = metadata !{metadata !5}
 !5 = metadata !{i32 720942, i32 0, metadata !6, metadata !"bar", metadata !"bar", metadata !"", metadata !6, i32 3, metadata !7, i1 false, i1 true, i32 0, i32 0, i32 0, i32 256, i1 true, void (i32)* @bar, null, null, metadata !9} ; [ DW_TAG_subprogram ]