[clang] [AST] Assert that FoldingSetNodeID used for hint is correct upon insertion (PR #157692)

[Erich Keane via cfe-commits]

erichkeane wrote:

> > Sensible? Or presumably we can have an always-inline function wrapper for that, and the inliner will just take care of it.
> 
> Yeah, I think the inline helper is cleaner, we can just discard ID before calling anything not inline.

Sounds good to me, an `always_inline` tagged one (there is a LLVM flag for it?!) would probably have no overhead as a result.

https://github.com/llvm/llvm-project/pull/157692