libstdc++: Fix std::is_nothrow_invocable_r for uncopyable prvalues [PR91456]
This is the last missing piece of PR 91456.
This also removes the only use of the C++11 version of
std::is_nothrow_invocable.
libstdc++-v3/ChangeLog:
PR libstdc++/91456
* include/std/type_traits (__is_nothrow_invocable): Remove.
(__is_invocable_impl::__nothrow_type): New member type which
checks if the conversion can throw.
(__is_nt_invocable_impl): Replace class template with alias
template to __is_nt_invocable_impl::__nothrow_type.
* testsuite/20_util/is_nothrow_invocable/91456.cc: New test.
* testsuite/20_util/is_nothrow_convertible/value.cc: Remove
macro used by value_ext.cc test.
* testsuite/20_util/is_nothrow_convertible/value_ext.cc: Remove
test for non-standard __is_nothrow_invocable trait.
(cherry picked from commit
71c828f84572d933979468baf2cf744180258ee4)