Rebased localmods in libcxx to 223109.

include/atomic

Index: include/atomic
diff --git a/include/atomic b/include/atomic
index b01a59f5f96f035887f595b0192a66cb677e0ee1..fe856093528d5c4968339db1b0e58bdfb598abf0 100644
--- a/include/atomic
+++ b/include/atomic
@@ -815,12 +815,24 @@ struct __atomic_base  // false
 {
     mutable _Atomic(_Tp) __a_;
 
+  // @LOCALMOD-BEGIN The NaCl builtin delays resolution of the lock-free
+  //                 property until translation time (time at which the
+  //                 actual target is known).
+#if defined (__pnacl__)
+    _LIBCPP_INLINE_VISIBILITY
+    bool is_lock_free() const volatile _NOEXCEPT
+        {return __nacl_atomic_is_lock_free(sizeof(_Tp), &__a_);}
+    _LIBCPP_INLINE_VISIBILITY
+    bool is_lock_free() const _NOEXCEPT
+        {return __nacl_atomic_is_lock_free(sizeof(_Tp), &__a_);}
+#else
     _LIBCPP_INLINE_VISIBILITY
     bool is_lock_free() const volatile _NOEXCEPT
         {return __c11_atomic_is_lock_free(sizeof(_Tp));}
     _LIBCPP_INLINE_VISIBILITY
     bool is_lock_free() const _NOEXCEPT
         {return __c11_atomic_is_lock_free(sizeof(_Tp));}
+#endif // @LOCALMOD-END
     _LIBCPP_INLINE_VISIBILITY
     void store(_Tp __d, memory_order __m = memory_order_seq_cst) volatile _NOEXCEPT
         {__c11_atomic_store(&__a_, __d, __m);}