[clang] [Clang] Apply exclude_from_explicit_instantiation to dllimport/dllexport (PR #168171)

[Tomohiro Kashiwada via cfe-commits]

kikairoya wrote:

> Or maybe we could use utils/update_cc_test_checks.py to auto-generate the test expectations?

Unfortunately, no. That removes the `declare` lines.

> Would doing -DAG checks help?

That doesn't work because `--implicit-check-not` seems to be ignored around `-DAG` checks.

> Or could we have fewer checks? This feels very complex given the functionality change.

Reduced a bit, and renamed to be more symbolic.
I'll try to reduce the noise further by splitting the files per class.

https://github.com/llvm/llvm-project/pull/168171