[clang] Re-apply "Emit missing cleanups for stmt-expr" and other commits (PR #89154)

[Utkarsh Saxena via cfe-commits]

usx95 wrote:

I have built a very large corpus with a clang built with these changes and run its tests. No compilation or test failures were reported. The corpus was built with exceptions disabled.
I am fairly confident in the correctness of this and will proceed with landing this patch for now.

That said, a breakage with missing destructors or double-free can likely be associated with this patch. Please report any breakages, especially with exceptions enabled.

https://github.com/llvm/llvm-project/pull/89154