[clang] [Clang] [Sema] Fix crash instantiating a member variable template partial specialization when the enclosing class template is deserialized (PR #202958)

[Shafik Yaghmour via cfe-commits]

https://github.com/shafik requested changes to this pull request.

Based on the current discussion to PR is looking like an extractive PR. Please step back make sure you reread the questions asked and actually understand the problem and any solution you propose moving forward. 

I appreciate that you want to make a contribution but if you need to do most of thinking here and use the LLM only as an assistant and not as a stand in for your understanding. 

https://github.com/llvm/llvm-project/pull/202958