[clang] [analyzer] Implemented the DanglingPtrDeref checker to detect use-after-scope lifetime errors (PR #209278)

[Balázs Benics via cfe-commits]

https://github.com/steakhal commented:

Still pretty good. It's easier to vet the code now that it's rebased. - I know it wasn't your fault.

https://github.com/llvm/llvm-project/pull/209278