[clang] [clang-repl] Extend the C support. (PR #89804)

[Vassil Vassilev via cfe-commits]

vgvassilev wrote:

> I was able to verify that the revert fixed the tests at least.

I am pretty sure that the failure ha to do with the incremental processing if-stmt in SemaDecl. I can provide a fix that does not trigger this for lldb but that would be a workaround. I suspect that change uncovers some inconsistency in either clang or lldb which I think we should fix.

https://github.com/llvm/llvm-project/pull/89804