While working on D53847, I noticed that this test would fail once we
started recognizing the types in the modified export statement .
The tests would fail because Clang would emit a "declaration does not
declare anything" diagnostic instead of the expected namespace scope
I believe that the test is currently incorrectly passing because Clang
doesn't parse the type and therefore doesn't treat the statement as a
declaration. My understanding is that the intention of this test case is
that it wants to export a struct type, which I believe requires a
struct keyword, even for types with template parameters. With this
change, the only error with these two statements should be the
namespace scope issue.