[llvm] [ADT] Use std::string_view inside StringRef (PR #113775)

[David Blaikie via llvm-commits]

dwblaikie wrote:

With inheritance I can sort of see the path forward to migration a bit (pending RFC discussion that that's the direction we're going in) - but with composition, I find it a bit harder to see the path forward.

Could you clarify what this migration looks like using composition instead of (or as a precursor to) inheritance?

https://github.com/llvm/llvm-project/pull/113775