[clang] [Clang] Permit noescape on non-pointer types (PR #117344)

[Aaron Ballman via cfe-commits]

AaronBallman wrote:

> > Why should this live upstream if it basically only benefits a single downstream?
> 
> This is a fair question, my intuition was that if the need came up multiple times independently, it might be worth to have it upstream. But it is also fair to wait until there is an actual upstream user, or multiple downstream users. I am OK with closing this and keep it downstream until either of those happens. The only risk is downstream users diverging, which is something we can always deal with during the RFC process before something is upstreamed.

My (slight) preference is to keep this in the downstream until we have a need upstream (or multiple downstreams need it). WDYT @erichkeane?

https://github.com/llvm/llvm-project/pull/117344