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

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GkvJwa wrote:

> Oh, your code wasn't blowing up in clang because you weren't using /EHa, which makes clang handle __try differently. Which makes it less likely to blow up, but also doesn't really work properly (see #62606).

Yes, Chromium does not enable /eha by default. This allows it to compile.
If using /eha, Before this patch, the compiled code might produce unexpected results. In other words, a real error might not throw an exception.

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