Recommit rL245802: Cleanup fancy pointer rebinding in list using __rebind_pointer.

Currently we need an #ifdef branch every time we use pointer traits to rebind a pointer because
it is done differently in C++11 and C++03. This patch introduces the __rebind_pointer utility to
clean this up.

Also add a test that list and it's iterators can be instantiated with incomplete element types.


git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@245806 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/containers/sequences/list/incomplete_type.pass.cpp

@@ -0,0 +1,27 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <list>
+
+// Check that std::list and it's iterators can be instantiated with an incomplete
+// type.
+
+#include <list>
+
+struct A {
+    std::list<A> l;
+    std::list<A>::iterator it;
+    std::list<A>::const_iterator cit;
+    std::list<A>::reverse_iterator rit;
+    std::list<A>::const_reverse_iterator crit;
+};
+
+int main() {
+    A a;
+}