[clang] [clang][scan-deps] Report a scanned TU's visible modules (PR #147969)

[Jan Svoboda via cfe-commits]

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@@ -519,6 +528,8 @@ class FullDeps {
                       });
                     JOS.attributeArray("clang-module-deps",
                                        toJSONSorted(JOS, I.ClangModuleDeps));
+                    JOS.attributeArray("visible-clang-modules",
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jansvoboda11 wrote:

I'm looking at it from the perspective that if I introduce a bug into the visibility logic, the test that I want to fail is `visible-modules.c`, not every other test under the sun. That reduces the noise and makes it easier to root-cause. The same applies when I'm working on some other feature (e.g. header search path pruning): if I introduce a bug, I'd like only for corresponding test to fail (`header-search-pruning-transitive.c`). If we feel the need for more coverage, I suggest adding more feature-specific tests.

https://github.com/llvm/llvm-project/pull/147969