Fix ambiguity in operator== of scoped_allocator_adaptor.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@131485 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/scoped_allocator b/include/scoped_allocator
index 70be28e..f361bcc 100644
--- a/include/scoped_allocator
+++ b/include/scoped_allocator
@@ -547,11 +547,11 @@
     return __a.outer_allocator() == __b.outer_allocator();
 }
 
-template <class _OuterA1, class _OuterA2, class... _InnerAllocs>
+template <class _OuterA1, class _OuterA2, class _InnerA0, class... _InnerAllocs>
 inline _LIBCPP_INLINE_VISIBILITY
 bool
-operator==(const scoped_allocator_adaptor<_OuterA1, _InnerAllocs...>& __a,
-           const scoped_allocator_adaptor<_OuterA2, _InnerAllocs...>& __b)
+operator==(const scoped_allocator_adaptor<_OuterA1, _InnerA0, _InnerAllocs...>& __a,
+           const scoped_allocator_adaptor<_OuterA2, _InnerA0, _InnerAllocs...>& __b)
 {
     return __a.outer_allocator() == __b.outer_allocator() &&
            __a.inner_allocator() == __b.inner_allocator();