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

[NAKAMURA Takumi via cfe-commits]

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@@ -573,6 +573,11 @@ struct EmptyCoverageMappingBuilder : public CoverageMappingBuilder {
 /// creation.
 struct MCDCCoverageBuilder {
 
+  struct DecisionIDPair {
+    MCDCConditionID TrueID = 0;
+    MCDCConditionID FalseID = 0;
+  };
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chapuni wrote:

I've forgot initial values are used as the default value in `createBranchRegion`. Sorry.

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