* testsuite/18_support/set_terminate.cc: Do not run for C++98 mode.
* testsuite/18_support/set_unexpected.cc: Likewise.
* testsuite/20_util/is_nothrow_invocable/value.cc: Test converting to
void.
* testsuite/20_util/is_nothrow_invocable/value_ext.cc: Fix constexpr
function to be valid in C++11.
* testsuite/26_numerics/complex/proj.cc: Do not run for C++98 mode.
* testsuite/experimental/names.cc: Do not run for C++98 mode. Do not
include Library Fundamentals or Networking headers in C++11 mode.
* testsuite/ext/char8_t/atomic-1.cc: Do not run for C++98 mode.
From-SVN: r271999
