Revert "Revert "Update aosp/master libcxx rebase to r263688""

This reverts commit 1d4a1edbc7.

Change-Id: I2909937fe582f2c5552bc86e7f4d2d5cff0de0aa

test/std/containers/sequences/array/array.swap/swap.pass.cpp

@@ -10,11 +10,23 @@
 // <array>
 
 // void swap(array& a);
+// namespace std { void swap(array<T, N> &x, array<T, N> &y);
 
-#include <array>
 #include <cassert>
+#include <array>
 
-#include "../suppress_array_warnings.h"
+#include "test_macros.h"
+
+// std::array is explicitly allowed to be initialized with A a = { init-list };.
+// Disable the missing braces warning for this reason.
+#include "disable_missing_braces_warning.h"
+
+struct NonSwappable {
+  NonSwappable() {}
+private:
+  NonSwappable(NonSwappable const&);
+  NonSwappable& operator=(NonSwappable const&);
+};
 
 int main()
 {
@@ -33,6 +45,22 @@ int main()
         assert(c2[1] == 2);
         assert(c2[2] == 3.5);
     }
+    {
+        typedef double T;
+        typedef std::array<T, 3> C;
+        C c1 = {1, 2, 3.5};
+        C c2 = {4, 5, 6.5};
+        std::swap(c1, c2);
+        assert(c1.size() == 3);
+        assert(c1[0] == 4);
+        assert(c1[1] == 5);
+        assert(c1[2] == 6.5);
+        assert(c2.size() == 3);
+        assert(c2[0] == 1);
+        assert(c2[1] == 2);
+        assert(c2[2] == 3.5);
+    }
+
     {
         typedef double T;
         typedef std::array<T, 0> C;
@@ -42,4 +70,24 @@ int main()
         assert(c1.size() == 0);
         assert(c2.size() == 0);
     }
+    {
+        typedef double T;
+        typedef std::array<T, 0> C;
+        C c1 = {};
+        C c2 = {};
+        std::swap(c1, c2);
+        assert(c1.size() == 0);
+        assert(c2.size() == 0);
+    }
+    {
+        typedef NonSwappable T;
+        typedef std::array<T, 0> C0;
+        C0 l = {};
+        C0 r = {};
+        l.swap(r);
+#if TEST_STD_VER >= 11
+        static_assert(noexcept(l.swap(r)), "");
+#endif
+    }
+
 }