[clang] [WinEH] Fix crash, object unwinding in the except block (PR #172287)

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MuellerMP wrote:

Ahh okay there is even more issues hidden here sadly: `__try`+`__finally` (`<PerformSEHFinally>`) uses `NormalAndEHCleanup` aswell and thus emits `seh.scope.begin` even though the state numbering algo ignores it.
This makes fixing this very tricky. I might take a further look as well once christmas holidays have passed.

https://github.com/llvm/llvm-project/pull/172287