[clang] [clang][dataflow] Treat comma operator correctly in `getResultObjectLocation()`. (PR #78427)

[Gábor Horváth via cfe-commits]

Xazax-hun wrote:

> This has been pretty lengthy, but I hope it gives more context.

Yeah, this was really helpful, thanks! This makes a lot of sense to me, I agree that this is a facility that we need. On the other hand, I am still wondering whether it is a good idea to expose this publicly to the checks or whether we could do it more transparently. That being said, I think the "publicness" of this API is not that important to solve at this point. 

https://github.com/llvm/llvm-project/pull/78427