[clang] [llvm] [clang][CoverageMapping] Refactor when setting MC/DC True/False (PR #78202)

[Jessica Paquette via cfe-commits]

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@@ -298,7 +298,7 @@ struct CounterMappingRegion {
                        unsigned ExpandedFileID, unsigned LineStart,
                        unsigned ColumnStart, unsigned LineEnd,
                        unsigned ColumnEnd, RegionKind Kind)
-      : MCDCParams(MCDCParams), ExpandedFileID(ExpandedFileID),
+      : MCDCParams(MCDCParams), FileID(FileID), ExpandedFileID(ExpandedFileID),
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ornata wrote:

Is this line the only bit necessary for the fix? Or are the other changes necessary?

If this is all that is necessary, then I would recommend splitting this into two patches.

https://github.com/llvm/llvm-project/pull/78202