[clang] [clang][SSAF] Optionally skip system-header contributors (PR #205446)

[Balázs Benics via cfe-commits]

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@@ -0,0 +1,43 @@
+// Regression for clang-reforge-7y4 / iter-03: end-to-end verification
+// of the --ssaf-no-extract-from-system-headers opt-out. Spec:
+// tu-summary-extraction's "System-header contributor opt-out flag"
+// requirement.
+
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steakhal wrote:

I think this part doesn't really make much sense upstream: `clang-reforge-7y4 / iter-03` etc.

https://github.com/llvm/llvm-project/pull/205446