[clang] [LifetimeSafety] Read lifetimebound attribute on implicit 'this' from all redeclarations (PR #176188)

[Gábor Horváth via cfe-commits]

https://github.com/Xazax-hun commented:

Could you summarize what was the reason for the crash and why was it not possible to work it around?

https://github.com/llvm/llvm-project/pull/176188