PR libstdc++/89416 fix accessibility of members

	PR libstdc++/89416
	* include/bits/alloc_traits.h (__is_alloc_insertable_impl): Make
	copy and move members public.

From-SVN: r269175

libstdc++-v3/ChangeLog

+2019-02-24  Jonathan Wakely  <jwakely@redhat.com>
+
+	PR libstdc++/89416
+	* include/bits/alloc_traits.h (__is_alloc_insertable_impl): Make
+	copy and move members public.
+
 2019-02-23  Jonathan Wakely  <jwakely@redhat.com>
 
 	* include/std/type_traits (__underlying_type_impl): New helper to

libstdc++-v3/include/bits/alloc_traits.h

@@ -590,7 +590,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       static false_type
       _M_select(...);
 
-  protected:
+  public:
     template<typename _Alloc, typename _Tp = typename _Alloc::value_type>
       using copy = decltype(_M_select<_Alloc, const _Tp&>(0));