[clang] [clang-tools-extra] Reapply "[Clang][Sema] Diagnose class member access expressions naming non-existent members of the current instantiation prior to instantiation in the absence of dependent base classes (#84050)" (PR #90152)

[Krystian Stasiowski via cfe-commits]

sdkrystian wrote:

@yxsamliu The call to `this->construct` in the `emplace` member of the partial specialization `class optional<T &>` _is_ a bug -- unlike the primary class template, the partial specialization for `T&` does _not_ inherit from `optional_operations_base` (which declares the `construct` member function).

https://github.com/llvm/llvm-project/pull/90152