[clang] [Clang] Preserve coroutine parameter referenced state (PR #70973)

[Bruno Cardoso Lopes via cfe-commits]

https://github.com/bcardosolopes commented:

Thanks for improving this! I haven't looked at your previous review of this PR, but I like the simplicity of this one. 

https://github.com/llvm/llvm-project/pull/70973