[libc++] Fix a missing include in pre-C++17 language modes.

var-const · var-const · commit 821513b1e663 · 2022-11-17T16:53:05.000-08:00
diff --git a/libcxx/include/__type_traits/noexcept_move_assign_container.h b/libcxx/include/__type_traits/noexcept_move_assign_container.h
@@ -12,6 +12,7 @@
 #include <__config>
 #include <__memory/allocator_traits.h>
 #include <__type_traits/integral_constant.h>
+#include <__type_traits/is_nothrow_move_assignable.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
