[C++ PATCH] Added test for c++/87250

[Matthew Beliveau]

My test is the result of reducing a file with just "include <atomic>",
just like in the PR.

It was fixed in r269059 which added a similar test, except mine does
not use inheritance and is a bit simpler. So I figured it wouldn't
hurt to cover more scenarios for this ICE.

I ran the test in my build directory and received 4 passes and 1
unsupported test, which was expected.
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