[clang] [clang] Fix loss of `dllexport` for exported template specialization (PR #93302)

[via cfe-commits]

zmodem wrote:

> Ok, I have confirmed that the getMostRecentDecl() fix does indeed work on the main branch.

Great!

> However, this fix also causes a dllimport test to fail too, so perhaps that was the "failure" that I encountered, I just don't remember.

Was this about `@_ZdlPv` in `clang/test/CodeGenCXX/dllimport.cpp`? Using `getMostRecentDecl()` makes that dllimport, and I think that's correct and matching MinGW's behavior: https://godbolt.org/z/Mzo1zGsrj

I think we should proceed with switching to `getMostRecentDecl()`. Either a new PR or continuing in this one works for me.

https://github.com/llvm/llvm-project/pull/93302