This shebang adds library tests for all cases of parenthesized aggregate
initialization that I could find. Tested locally on Linux-x64, going to
test with full suite on Linux-PPC64, OK for trunk if tests pass?

2020-02-23  Ville Voutilainen  <ville.voutilainen@gmail.com>

    Library-side tests for parenthesized aggregate init

    PR c++/92878
    PR c++/92947

    * testsuite/20_util/allocator_traits/members/92878_92947.cc: New.
    * testsuite/20_util/any/assign/92878_92947.cc: Likewise.
    * testsuite/20_util/any/cons/92878_92947.cc: Likewise.
    * testsuite/20_util/is_constructible/92878_92947.cc: Likewise.
    * testsuite/20_util/optional/assignment/92878_92947.cc: Likewise.
    * testsuite/20_util/optional/cons/92878_92947.cc: Likewise.
    * testsuite/20_util/pair/cons/92878_92947.cc: Likewise.
    * testsuite/20_util/shared_ptr/creation/92878_92947.cc: Likewise.
    * testsuite/20_util/specialized_algorithms/construct_at/92878_92947.cc:
    Likewise.
    * testsuite/20_util/unique_ptr/creation/92878_92947.cc: Likewise.
    * testsuite/20_util/uses_allocator/92878_92947.cc: Likewise.
    * testsuite/20_util/variant/92878_92947.cc: Likewise.
    * testsuite/23_containers/deque/modifiers/emplace/92878_92947.cc:
    Likewise.
    * testsuite/23_containers/forward_list/modifiers/92878_92947.cc:
    Likewise.
    * testsuite/23_containers/list/modifiers/emplace/92878_92947.cc:
    Likewise.
    * testsuite/23_containers/map/modifiers/emplace/92878_92947.cc:
    Likewise.
    * testsuite/23_containers/multimap/modifiers/emplace/92878_92947.cc:
    Likewise.
    * testsuite/23_containers/multiset/modifiers/emplace/92878_92947.cc:
    Likewise.
    * testsuite/23_containers/priority_queue/92878_92947.cc: Likewise.
    * testsuite/23_containers/queue/92878_92947.cc: Likewise.
    * testsuite/23_containers/set/modifiers/emplace/92878_92947.cc:
    Likewise.
    * testsuite/23_containers/stack/92878_92947.cc: Likewise.
    * testsuite/23_containers/unordered_map/modifiers/92878_92947.cc:
    Likewise.
    * testsuite/23_containers/unordered_multimap/modifiers/92878_92947.cc:
    Likewise.
    * testsuite/23_containers/unordered_multiset/modifiers/92878_92947.cc:
    Likewise.
    * testsuite/23_containers/unordered_set/modifiers/92878_92947.cc:
    Likewise.
    * testsuite/23_containers/vector/modifiers/emplace/92878_92947.cc:
    Likewise.