[clang] [clang][DependencyScanning] Track modules that resolve from sysroot. (PR #130634)

[Cyndy Ishida via cfe-commits]

cyndyishida wrote:

> I have a similar concern to @jansvoboda11 that we probably need to check the invocation paths as well.

> The situation this covers is how likely is it that the build system is going to determine this needs to be rebuilt, and that happens (in most cases) purely based on the reported dependencies.

I can add the checks for inputs through the compiler invocations, with the hope that it will allow for more pcm sharing across build plans (e.g. projects) depending on the same modules. I am a little worried that a more conservative check would mean fewer modules that otherwise could safely be in a shared location don't end up there due to other limitations (e.g. we don't prune out an option that is safe to), but I don't have a sense if that is a practical concern.

https://github.com/llvm/llvm-project/pull/130634